Topic: Coinplate Steel Seed Phrase Saver (Read 925 times)

OK. Can you tell us how you would recover a seed that was written down on paper and got lost? Or how would you recover a seed stored digitally (not recommended) if you can no longer gain access to that medium? Let's assume in all cases that you only have that one backup. The one that's lost.

It's a phrase or a seed, not a phase. Coinplate is just a metal plate where the words can be written down. It's not a wallet. Your seed can be stored on metal, paper, wood, concrete, as a tattoo on your arm... If you lose it, you lose the possibility to recover your coins if needed. You can still move your coins if they are in a fully functional and configured software/hardware wallet even without the seed. 

Are we still talking about a situation where you lose the entire seed or what are we talking about?

With non-custodial solutions, there is no support center to call. You control your money, you protect it, and only you should have a copy of your recovery phrase. There shouldn't be anyone to call when it comes to Bitcoin. If there is, you are doing many things wrong. 

My comrade, you are out of point from the whole topic and discussion here. We are not taking about recovering of seed phrase here but where to keep it in a safe place. That is why Coinplate Steel is recommended so if anyone is interested can order and get it from the company so you are not to hit or click any forgotten password link. Please you can look for a board that is suitable for you because your idea is contrary here. please don't be offended. thanks

That's not the case for the method that foggoat proposed. In his example, each share contains 16/24 words and any two shares will have all the words necessary to recover the seed. Losing one share still leaves two splits that can be used for wallet recovery.

So if we were to rank the different splitting systems from 1-4, the worst one would be to split 24 words on three and backup 8 words on each split. In that case, losing one share means losing your coins. In 3rd place we would have foggoat's example with 16 words per share. SSS would take the 2nd place. And using multisig is still the best way to go about it.

It would be nice to know foggoat's opinion on this matter and whether they can indicate to their customers on declaration paper a minimum of information about the content, of course, without telling what is inside. Also, it would be better not to indicate the name / logo of the manufacturer on the package / declaration paper and this applies not only to the Coinplate company. What do you say to that, foggoat? The name of your company leaves no doubt what is inside the package. This is not only for you, but for most of your competitors too.

Drifting way OT, but in a lot of new construction you see metal mending / binding plates where 2 pieces of lumber meet:

https://www.homedepot.com/b/Building-Materials-Building-Hardware-Mending-Plates/Prong-Plate/N-5yc1vZasc4Z1z1at5c

Nail them together and then use these for more support so metal that can be found with a metal detector in walls is not a big deal in a lot of locations.
With that being said I think in most locations a piece of metal like this is going to be unnoticed.

Which is more obvious, something like a seed place or hardware wallet sitting in a safe or a seed plate screwed to the underside of a couch so that it looks like someone did a quick and dirty repair?
Which I may done with a normal piece of metal I found.

Makes you wonder if someone could make a seed plate that is 'aged' to look like a piece of junk metal that has been sitting around since before the home PC existed, never-mind BTC

-Dave

Problem I see with splitting seed phrases in any other way than good multisig setup, is that you will have single point of failure.
Losing single part of split seed words would mean you will lose all your coins and all other parts would be useless.
I could say similar thing for Shamir Secret Sharing, it also has single point of failure.

All they need is metal detector to see if something is hidden inside walls or floor, so I think this could be main negative side of using any metal based seed words backup.
I am not saying someone would scan for seed words with metal detectors, but they could used them to scan for other precious metals, so this this would be biproduct.

It's much less dangerous than buying hardware wallets, since this is just a piece of metal and there is no direct connection with Bitcoin.
You could probably ask them to write on declaration paper it's just a metal plate for home use.

Yeah, don't get me wrong here. I'm not criticising that they're doing this (I quite like that these type of services/products exist), I'm just suggesting those that are willing will find easier ways of going about this, with less security risks, and more convenience. The security risks aren't all that much as has already been discussed, for example using PO boxes for both security, and privacy is probably wise.

As suggested above their markup isn't crazy, and does save you some of the effort yourself, so definitely the local metal works route is definitely for the Do It Yourself (DIY) type of people.

Shipping physical, clearly Bitcoin-related products (and other goods, too) is always an area of concern.
Price-wise though, I just checked and their markup is actually not too high, considering the extra work for the milling, tapping and engraving. Though if you don't need that, you can get away a good chunk cheaper by getting the steel cut locally.

Coinplate:

Random piece of AISI 304 on a general metal store (probably similar to local hardware store prices):

For any product there is always a buyer. Accordingly, there is a corresponding demand for products, such as coinplate, even at declared prices. For people like you, who are able to make an coinplate's equivalent with the tools and materials at hand from the nearest shop, coinplate seems overpriced. But it should be borne in mind that not everyone has such skills and the desire to actually make seed phrase saver like coinplate by hands. It seems to me that the coinplate and analogues of other competitors are aimed at such buyers. I almost forgot to point out that they are also ready to expect delivery (buying locally is incomparably faster) and neglecting the safety of personal data, such as payment details (if you pay not in cryptocurrency) and delivery address. Buying locally leaves no "trace" that you bought the coinplate and respectively, you are the crypto owner.

Yeah, your house footings even if it was a fire or what not probably aren't going anywhere any time soon, so cementing in concrete is a decent idea. Plus, no one's going to be digging that up while you're there, unless someone pulls some Prison Break esque plan on you, but that's incredibly unlikely.

However, while it's nice that this product exists, and I know the costs have been figured out a little more since the OP, I can't help, but think I could just go to my local metal works shop, and get something of similar quality for much less, and wouldn't need to ship it. Obviously, you could argue that your local metal works could be using lesser metal, but you could potentially test it yourself to assure that. So, this product is decent for those that can't find any other means, but it's still rather expensive when you factor in almost everyone has access to this sort of thing locally at a reduced cost.

It's not 8 words per seed plate, it's 16 words per seed plate. 8 words in total are missing from each share. No matter which two shares you have, you will have all the necessary words to restore your wallet.

I agree with Andreas in the sense that a seed shouldn't be split up because losing one part can create plenty of difficulties. In this particular example, losing one split wouldn't do that because you still have two remaining. And any 2 out of 2 shares are enough for wallet recovery. I am not sure what you can do with today's technology and how far we are from being able to bruteforce 7 or 8 words. But no matter how easy or difficult it is, bruteforcing 8/24 is exponentially faster than cracking all 24.

foggoat method isn't bad in the sense that it's ridiculous. It isn't. If you split your seed in the way he suggested and someone finds one of your backups, he would have 16 out of 24 words needed to steal the coins. If you have 3 different backups with all your words written down on all 3 pieces of paper and one of them got stolen, the thief would have everything they need to get to your coins. In that sense, it would have been better to use foggoat's splitting system.

But why give a thief even 16 out of 24 words if you can do it in a better way? With SSS, finding a share that is below a quorum, is like having found nothing at all. Even better, finding 1/3 of a 2/3 multisig gets you no closer to the coins because you need 2/3 to spend the BTC. 

Ok. You suggest splitting seed phrasee into 3 parts and storing it in 3 different places. It turns out, 8 words for each coinplate. Then it would be right to add mini-coinplate (like coinplate split - I don't need thanks for the name I came up with for your new product line ) to the assortment of your store. A smaller version of coinplate with space for 8 words and offer them in packs of 3 (for 1 to 8, 9 to 16, 17 to 24 words).

I don't undertake to discuss the correctness of dividing splitting seed into 3 parts, since, for example, Pmalek believes that this is a bad idea (not only he thinks so).
Let's leave the right to choose exactly how to store their seed phrase, splited or whole for the owners of it personally.

I want to say the following. If foggoat voices this method, then it would be logical to offer his customers to purchase a product that allows you to split seed into 3 parts. Those samples that are available in the https://getcoinplate.com/ are not suitable for this (it contain space for 24 words) and buying 3 coinplates to fill only ~30% of the surface of each I consider wasteful. In total, 3 such plates will cost ~200-240 euro (Punch version or Alpha). Offer buyers 3 mini-coinplates for 8 words for the approximate price of one coinplate (~70-80 euro). Then this will be useful, otherwise it turns out that you offer this method of spliting seed into 3 parts only in order to increase your sales (selling 3 plates is better than 1, right). No offense. I expressed my subjective opinion.

OFFTOPIC
I absolutely disagree with his explanation and his recommendations. You can check the comments to see that he couldn't really prove his point in that video. Also, I think that you miss the entire point here. I'll stop at that as it's not the topic here...

I read your replies and I understand you are just suggesting an alternative and not saying that it's better than this or that. I like this video of Andreas Antonopoulos who explains why seed splitting is a bad idea: Bitcoin Q&A: Why is Seed Splitting a Bad Idea?

His exact words is that the suggested splitting method is absolutely not safe and that people should never make such custom shares and store them separately. He does go on to suggest that SSS is a better solution than custom-made splits because if you have less words than the needed quorum in SSS, its like you don't have any words at all. But having knowledge of 16 words like in your example makes it exponentially easier to bruteforce the remaining 7 or 8. 7 because the last word is a checksum, so it's easier to guess that one. Andreas also suggests that in the next decade, it should be possible to bruteforce 7-8 words with powerful-enough machines.

True; I got sidetracked a little bit. I guess both have their benefits and drawbacks. 3 full seed backups means almost guaranteed not to lose funds, while not being hackerproof at all.
Your method would be more secure against an attacker / if someone found one backup, however the owner may lose 2 backups and lose all their funds or they could forget how the scheme worked and not be able to recover it.

The reason why me and others 'quickly' bring up multisig is that it's less hard / scary to set up and use as some may believe & it's popular; you can see in this forum alone how from time to time people come in asking for help with their custom-seed-backup that they can't restore anymore.

No worries! Just want to make sure before you recommend custom backup schemes to customers that they are aware that we already have tried, tested, documented and popular schemes (maybe a little more effort to set up) that they could have an easier time recovering, years down the line. If not just because they are more common.

Sorry about the off-topic!

No problem, that would be dumb. No one should straight split their seed, I agree.


The multisig is a solid approach, I cannot argue with that. Not meant it to be a multisig alternative, but as a whole Multisig is still more complicated than the simple approach I suggested. The scheme I suggested can be explained in a few sentences and solid, durable backups are easy to make. However, multisig needs a detailed tutorial and compatible wallets. It might be difficult to remember it all after a few years or if your family member would ever need to access your coins.  

Most importantly, the discussion started from just simply keeping the extra backups of your seed phrase, not making it totally hackerproof or other things if I recall correctly.

If you were to keep just 3 straight backups of your seed phrase in separate locations, you will be better off using the scheme I suggested. In the thing, I suggested If someone found one of your backups you will be safe from hacking for quite some time (at least a few months if not years), it will require some proper knowledge and resources (incl. time) to crack it. Furthermore, I haven't mentioned this idea as any sort of alternative to a multisig, as it's a whole different beast altogether, and I don't really follow why we are discussing it that way.


Probably, true. However, the approach I suggested is quite simple so probably no true need for a lot of explainers. As mentioned earlier multisig is still a more complicated thing.



Honestly, I haven't thought that someone might still make a wallet with 12 words nowadays, it's not a good practice. I mentioned 24th words seed in my example.
Cracking 4 words of BIP39 seed is hardly comparable to cracking 8 words. To crack 4 words you need around 2^40 combinations, for 8 words it's around 2^80, it's a completely different thing. ^{(not really precise math here though)} You will have 7 words to crack on one of the backups as the last word is a checksum, but it's not that much difference.
It will take quite a lot of knowledge and computing power +money  to crack 8 words and it still will take months if not years. Also they will need to get one of your backups in their hands first.  

And as we were discussing just a mere alternative way of keeping your multiple seed backups in different locations, I think that's quite good for something that is so easy to do.
Even for 12th words (which is not ideal) it still beats keeping multiple backups straight and fully, as it requires proper knowledge to crack even 3 or 4 words. A bit harder to do than just putting the words into a wallet.  Overall multisig will offer probably much better security, but a bit more complicated to do properly.

I am not arguing that one is better than the other, though. I'm not pushing anyone to use that scheme. Different things for different folks. Never meant it as an alternative to multisig. Just replying to your arguments.

It is a simple no-tech idea meant as a way for keeping multiple seed backups in separate physical locations, where you are not able to keep an eye on all of them for 24/7.  
This is quite a digression from the main topic and maybe it would be best to not make this the center of this thread and avoid jumping into this rabbit hole.

Sorry; misread. I thought you'd recommend splitting 1-8, 9-16, 17-24.

As gmaxwell said, though, I don't understand why. There are so many good guides for setting up Multisig with basically any software and hardware wallet and combination of them.
A nice side effect is that you can deposit dummy amounts on each individual seed to deter any thief / finder to go looking for a second seed.

And also.. it just works, it's integrated into wallets and it's a popular scheme, so if someone has a problem with setup or restore, they'll find help online without a problem.
I can almost guarantee that they would find less users who know about this '1-16, 9-24, 1-8 + 17-24' scheme and who will be able to assist.

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I haven't calculated it with 24 words, but it appears that if someone found 2/3 of the words of a 12-word seed phrase (8 words), it's possible to crack the remaining 4 words rather quickly.
https://bitcoin.stackexchange.com/a/101336/119879

Basically, in your scheme, each share holds 2/3 of the original seed's key material.

Have you even taken a minute to think about it or just straight assumed it's wrong? The thing is it's a 2 out of 3 scheme, you need to lose 2 parts out of 3 to lose your seed phrase. If you lose just 1 part out of 3 you are safe and sound.

I'd also advocate for Multisig instead of SSS. It was discussed on this forum at length, a whole bunch of times and if memory serves correct, Multisig always came out on top.

Even Gregory Maxwell himself seems to agree with this:
[emphasis mine]

That's actually even worse! If you lose 1 part, the whole thing's gone. Never do that!

I didn't mean Shamir's Secret Sharing, it's probably too complicated for most of ppl including myself. Not a biggest fan of multisig, but it might be nice if you have a big holdings.

I meant just very simple idea that you just split your seed into thirds. Then each copy has 2/3 of the full seed on itself. You just do it manually, no tech no math approach. For example 1st copy has words 1-16th, 2nd has 9-24th and 3rd has 1-8th + 17-24th. I think that it's simple and it works, it might be good enough for most long term hodlers.

Sounds like you are talking about Shamir's Secret Sharing. The problem with SSS is its single point of failure. The splitting part is done on a single device and the reconstruction of the shares is also done on one device. That's the single point of failure. Jameson Lopp talks about it in detail here. A standard 2/3 multisig setup sounds like a better idea.

About PO Boxes, we currently ship to post boxes that are freely accessed by third-party delivery companies like FedEx. This mostly includes mailboxes or virtual mailboxes that are operated by some 3rd party private companies. For the moment we might be unable to deliver to some post boxes that are operated by post operators like USPS in the USA, as they don't allow other operators to access them.  If you think this is something that might be desirable by some customers, I think we can look into adding international post/mail delivery, which should be able to reach regular post boxes. For most folks, it would be not an ideal option, but maybe for PO Box delivery, it would be beneficial.


Regarding the data. I am aware that data security is an important thing. We are not that big but we do take some measures to secure the data.
Currently, we offer everyone (not just EU-based customers) to ask for full erasure of their personal data and transaction details after the return period is over. A significant % of our customers ask us to do so right in the order form. This includes all data on our servers as well as all e-mail messages.
As an EU-based company, we are obliged to follow strict GPDR law, that requires us to delete all your data on your request. Also, it allows us to request the same on behalf of our customer to third parties like payment processors and delivery companies, which we do as well. We don't keep data at 3rd parties aside from our servers. Also we purge the database manually every few months, as I don't like the idea of hoarding the customers data indefinitely.
The only data that remains at us then are obligatory tax records i.e. receipts but we move them to offline and/or paper storage periodically which is kept in a separate physical location.
 
I am looking into making this process fully automatic which will allow us to, by default, delete everyone's data after 30 days from the delivery. It involves some work so it will take some time to implement, privacy policy needs some legal work too. We'll announce when it's ready. Probably then if someone opted in for a newsletter or sth we will just keep their e-mail address but nothing else.

^{Open to all suggestions for improving the data security.}


That's right. What I might recommend is to have your seed splitted in 2/3 way, which means you can read your seed while having any 2 out of 3 copies. Yet with only one of copies you cannot get the seed as it will require you to crack 8/24 of seed which still will take at best months if not few years. This requires having 3 safe locations, possibly different physical addresses. You should have them in a place where you can check each few months if it was untouched, for total peace of mind. ^{It's easy to do, but If you need details I can give you some instructions if you PM me. I'll probably make a tutorial at our site in the future too.}



Forgot to add previously that shipping to some remote or expensive locations is $19 instead of regular $9. Edited the original reply accordingly. This includes countries like Autralia, New Zealand, islands in the middle of the sea, Switzerland, Norway, some African and Asian countries. You can get the delivery price from the product page or checkout. Still it is free for orders everywhere over $100 like you just pointed out.

Please be aware that in some countries you can get charged by local customs office import tarriffs, tax or duties at delivery. We listed info about some most popular destinations at our site, but in other cases you should check how it looks like with your local customs office. Maybe that's what the OP, Agbe meant? I believe it could add up to $50 with $270 value in some cases.


Also it might be important to some folks here, especially in US market, that all prices at our site include all sales taxes so the prices = amount paid.

The problem is that $276.00 is for 5 plates and you made it seem like you paid that amount for a single one.
And it was confirmed that shipping is FREE worldwide above $100; you can't just come up with a random figure - and say that you paid $50 on top of the $276.00, as that's impossible even if you got the 5-pack.


Sorry that I'm getting mad, I just hate misinformation.

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I just played around with the country selection, and if you get a single plate (under 100€), then shipping to some African states (haven't tested all of them) is 19€. You don't have to leak your location of course, but I just think $50 shipping for one plate is too expensive and just doesn't make sense / wouldn't be offered, if you can get e.g. a 3-pack for 189€ and have free shipping.

@foggoat
Can these units be shipped to PO boxes and how do you handle private information of your clients?
Is it deleted and wiped altogether from servers, how long is it stored, and do you self-store data or rely on a 3rd-party?

Hacking or leaking information about thousands of users who have ordered steel plates could be a valuable piece of info and a dangerous hit list of sorts. Not just from your company, but in general.   

https://getcoinplate.com/product/coinplate-alpha/

This is the price in the website. The shipping fee down to my community is high within my country and this will come from outside country. So I only add $50 for the $276.00 base in the distance though that might be wrong from the calculation.

That's some serious density and heat resistance!

While I'm still a big fan of the 'DIY washer method' (there's no metal seed phrase backup, remotely as cheap) - since a coinplate does not cost $300 USD, I may consider it in the future for a very 'heavy' (packed with good amount of coins) Bitcoin wallet.
Though if just your own house burns down (not a huge apocalyptic sized fire), you should have redundant seed phrase backups elsewhere.

Buried under the basement / in the cement sounds like a good idea.

You can read our comments on the tests in our blog post. The units that Jameson Lopp tested were shipped to him around half a year ago. Since then we improved the manufacturing a bit, so the screws are not as tightly fitted as before. It should mitigate some of those problems.

However, the important thing is that Coinplate will survive a house fire, even if it's abnormally hot. House fires burn at around 600°C/1100°F (at max can get up to 850°C/1500°F), and it survived a much higher temp of 1093°C / 2000°F in that test quite fine.


The most important thing for a backup is to survive and protect your seed phrase. If after a terrible disaster your only worry is to open your quite intact backup I think that's great.  Even if it may require using some extra force, a hammer or maybe a power tool in some worst cases.



My finger must have slipped, I meant 1.1kg. Yeah, that's how much our backups weigh. The weight of each is between 1.13-1.14 kg.
You don't have to just trust me, you can make the calculation yourself using for example this steel weight calculator. The dimensions for the whole unit are 10 x 105 x 138 mm. The material is 304 stainless steel which is stainless T-304 in this calculator. The calculator computes the weight as 1.16 kg or 2.56 lb, but there is some slight material loss during the processing (i.e. rounded corners, mounting holes, polishing). Screws fill their sockets almost entirely, though.



That's the same conclusion we have arrived at, after making some mockup designs. Glad that I helped and thanks for the interesting discussion.


Sorry for that dumb error on our site and inconsistency. As explained above, each Coinplate weighs between 1.13-1.14 kg. Thanks for pointing it out though, I'll review our site for errors.

They seem to be using different numbers on different parts of their website. The main page says it weighs 1.3kg:
https://getcoinplate.com/

But if you check each product separately, you are shown the number you mentioned.
https://getcoinplate.com/product/coinplate-punch/?attribute_pa_bundle=none
https://getcoinplate.com/product/coinplate-grid/?attribute_pa_vp=single
https://getcoinplate.com/product/coinplate-alpha/?attribute_pa_vp=single

This additional information changes everything. I can say that your products don't stand out much from competitors in terms of price, as OP originally voiced about 300$. I don't know why this erroneous figure was indicated, but now everything is clear that it was just a mistake.

A little quibble, to be meticulous. On your website, the weight is 1.14 kg.

Is the total weight of the plates really just over 1 kg? I can't imagine that plates with the indicated dimensions weigh so impressively (of course, relative to another).

It was just my idea. Probably not the best. After reflecting on your answer, I came to the conclusion that an additional layer of additional material between the plates would be unnecessary and would create the risk of breaking the plate. Silicone or rubber doesn't have the same high resistance to various media as stainless steel, which means that if exposed to adverse conditions, it will be destroyed faster than plates. This will lead to the fact that an "aggressive" substance can penetrate into the gap between the plates, which will put this storage medium at risk. This is my verdict after theoretical considerations.

Thank you for your very detailed answer and detailed explanations. This allowed to look at your product from a different perspective.

It's nice of you to chip in and share some additional information, particularly about Jameson Lopp's new tests. They seem to have performed nicely although there were problems with the heat stress tests with both the Coinplate Alpha and the Coinplate Grid. He had difficulties unscrewing the fasteners and taking the plates apart, but in the end he managed to do it.

Hello everyone, as a founder of Coinplate I would like to join this discussion to clear some things out. There were some misunderstandings about our products. If you have any further questions, I'll do my best to answer them.
There is also my separate thread about Coinplate the seed phrase storage solution, if you would like to get more details and perspective.


Some of the photos that OP - Agbe posted are actually not of our product. Some of them are from other companies. You can check our products at our site getcoinplate.com. Sorry, but I cannot post photos yet.

m2017 correctly identified our products at our site:


Actually, our products start at $65 and international shipping is quite cheap. Wordwide FedEx shipping is $9 and we ship our products literally everywhere in the world. (apart from Russia obviously)
Furthermore, You can get bundles that let you save a bit. For example, Coinplate Alpha costs $79, the 3 Pack is $189 (20% off) and 5 Pack is $276 (30% off). That's probably where this incorrect $300 price tag came from. And you get free worldwide shipping with orders over $100. €1 is now worth $1 at our site as that's how exchange rates look like right now.
EDIT: Forgot to add that shipping to some remote or expensive locations is $19 (i.e. Australia, Switzerland). Still free worldwide shipping for orders over $100, also to these locations.
 
To put the price of our products into perspective, some of the more known brands on the market are priced at $130 or more for a single backup and they don't offer that high durability in my opinion.

Coinplate is made using 2 thick stainless plates joined with solid screws that are set using threads in the plates, without a separate washer. Each Coinplate weighs 1.2kg / 2.5 pounds, so you are getting quite a heavy-duty unit. It is a stainless steel sandwich made from two plates each 5mm (3/16") thick.


Our products do not feature an extra, special space for 25th word (aka passphrase) and in all our communication we inform our customers that the passphrase should not be kept together with your seed phrase for security reasons. In every instruction manual in the box, we include some seed phrase safety tips, where we inform that a passphrase should be kept in a separate location and a backup should be made on a separate unit. Coinplate Punch has some additional spaces for memos and info, though. It is possible to make a backup of the passphrase on either Coinplate Alpha (if you use only letters of the same size) or Coinplate Punch (all symbols capable).



If anyone would rather make the backup themselves, go for it. I myself also like to DIY stuff in my house, but obviously not everything. People don't have to make themselves everything they use, there is room for both ready made stuff and DIY.

If you want something ready-made and super easy to use, you may just order something that's made like that - Coinplate Alpha, where you just press the center punch. No risk of smashed fingers. Also no other tools needed, as everything is included, so you can start right away. Anyone can do it on their office desk in just few minutes. It might be a bit more expensive than getting some thin plates from a hardware store or a set of washers, but remember that your time costs too and tools are not free either. Plus you get something of much higher quality and durability at the same time.

Also for Coinplate Punch we give an option of getting a bundle with an electric engraver, a bit more easy to use option than hammer +  stamps but it's up to you. We also ship bundles with stamps.



We did tinker with this idea actually. The thing is that when you screw the plates together, they are pretty tight themselves, so any corrosive agent has a hard time getting between the plates. Furthermore, even high-strength acids don't really affect the markings, even if the device is left open. The layout is deep engraved and the marks you make yourself are also pretty deep. You can see that it survived acid in Jameson Lopp's stress test. The gasket would itself be vulnerable either to fire, oil or acids (there are some specialized gasket materials but they are nowhere near the durability of stainless steel, we know as we make some industrial grade gasket ourselves).



Jameson Lopp have just recently stress tested our products, all of them received the top A A A rating.
Coinplate Alpha test, Coinplate Grid test, Coinplate Punch test and our blog post with a comment.



The logo on the front is just a sticker that can be easily removed if you like. After you do that, Coinplate looks basically just like a piece of scrap metal, and you can hide it pretty well if you think about it. The tamper stickers are obviously not mandatory, just an extra that's included in the box. Furthermore, the tamper stickers' material and color are almost the same as the metal itself so they blend quite nicely.

Plus you can literally get your Coinplate secured in the foundation of your house and covered by a wood floor if you wish. It has an extra set of holes so you can fix it securely with some proper anchors. It should also survive disasters, just like the safe you mentioned, if not even more. Paper kept in a safe might not survive a house fire, but your Coinplate will.


Hope I covered most of the topics mentioned here, if not, ask me anything you like.

I tend to disagree with such a broad, generalized answer. There are definitely reasons for keeping the passphrase together with your seed words.
A few examples where the passphrase is not used to make the seed backup useless when found.

• Passphrase is used for plausible deniability. When someone finds / hacks your wallet (software or hardware), they only see a small amount of funds, but you can restore the hidden wallet with your 25 words.
• Passphrase is used to protect against flawed / purposely reduced entropy of wallet's seed generation process (or malicious wallet with deterministic seed generation).
• Passphrase is used to separate wallets that are still tied to 1 seed (e.g. different 'accounts' with different purposes on a single hardware wallet)
• Passphrase is used to simply add more entropy.

I'm sure there are more use cases for the 25th / 13th word in scenarios where you assume that your seed backup is protected (just as if not using a passphrase), where it gives you a different benefit instead.

The mnemonic passphrase field shouldn't be there at all. By its existance it could spark a very bad idea into less informed users, who might think it's ok to save and store it together with the mnemonic seed words.

It's just a terrible design decission and frankly I have no words for it that this company dared to do it like they did.

But again when we think about it, how many people even know what a passphrase is and use that option - whether it's a desktop or a hardware wallet? Even if they know what a passphrase is, do they know that it is not wise to store seed and passphrase together? Therefore, I think that the majority will leave that field empty and that it is not a big problem.

However, users should be informed about the best security practices when using any crypto wallet or backup method, because regardless of how good the tool is, people show that they forget over time like that character who forgot a fairly simple screen pattern and thus locked his crypto wallets.

He might have ordered a 3-Pack or a 5-Pack, hence the price. The company sells 3 different type of products priced between €62 and €76. A 5-Pack costs €263 for the most expensive plate. But the website also says that if offers free shipping at that price. Agbe is from Nigeria I think. Not sure why he was asked to pay another $50 for shipping. Standard shipping to Nigeria is €19 for one metal steel plate.

Good point. I didn't even consider that when I wrote that post you quoted. You are absolutely right, it shouldn't be there at all!

Seed and passphrase should not be on the same backup anyway, because in my opinion the goal of protection with an additional word is to make seed completely useless in case someone finds it. In my opinion, this field is completely unnecessary and may even lead people in the wrong step.

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Most plates for backup do not offer the possibility to write the whole word anyway, but the first few letters of the word are enough, which will then be recognized when entering into any good crypto wallet. If you have ever done wallet recovery on a hardware wallet, then you could see that after entering 2-3 letters, the device offers a word - so for 24 words, it took me less than 5 minutes.

Wow; first thought: that's a lot of money for steel backup plates! People even find Passport hardware wallet too expensive and it costs less + it's an actual electronic device.
I'm still a big fan of the washer method, because it's so cheap that you can do multiples and spread them, like BlackHatCoiner suggested with paper backups.

Regarding resistance against the elements, sure there are more premium materials that withstand more (heat, acid, ...), but again it's cheaper to fight risk of destruction by means of redundancy.
Another point against using a commercial seed backup is that obviously you leave more traces; such as Google cookies which notice you browse for such products, potentially ISP knowing you're interested in this product, shipping company and maybe even customs if it has to be imported.

One positive thing I noticed, though: I have made 'plate backups' before I came across the idea of using washers, so I highly recommend to use thick plates like shown by Agbe, if you like this more compact form factor, because if they're too thin, they will bend 'towards' you when hammering. So that's a thing which is great to see on this product.

According to their website, it is from 76-276 usd
 https://getcoinplate.com/product/coinplate-alpha/

Frankly,  this is a total waste of money. You can buy a computer with that money

Just write the seed down in a piece of paper and put some plastic in it. That is the most used and the best way to store your seed.

Make some copies and check them from time to time... no need to buy this.

From your post, I didn't understand (or missed) which particular model Coinplate did you choose? Alpha, Grid or Punch?

How about putting some material (rubber, silicone or something completely different) between the two plates for additional protection (at least around the perimeter) to prevent corrosion?

p.s.
~$300 is way too expensive for a simple piece of metal, even if it's stainless steel, and with bonuses like a couple of bolts, a marker, and other stuff that's sold at any hardware store.

When I look at things like this I see them more as designer safes as opposed to an old school one that is secured in the foundation of your house and then covered by a wood floor and a rug.

Just in general in a smash and grab it's a lot more likely to be found and taken then something that is a bit more generic looking.
And yes you can secure it to the bottom of a table but then why the tamper stickers. If for some reason someone sees it they might ignore it.
Ohhhh....a tamper sticker, I wonder what is inside of it......

-Dave

Doing verification tests (https://jlopp.github.io/metal-bitcoin-storage-reviews/why) yourself or sending them to be tested by specialists will earn them a good reputation.
Here is a list of good services (https://jlopp.github.io/metal-bitcoin-storage-reviews/) and some tips if you want to buy or check that the tool you used will really help you if disaster strikes.

The recommendations are:

• Simpler is better - more pieces means more potential points of failure.
• 304 Stainless Steel is the best.

I somewhat still feel it's unnecessary to use a steel saver. Just write it on a paper and spread it across locations so that if one's lost, you can have the backup(s).

Not just for the 25th word, even for regular words, the space might not be enough. For example, words like "business", "disagree", "february", "innocent" or "language" might just not fit. Definitely for the 25th word, though. Is it more important to have a Wallet Name than a strong passphrase? 

I am not familiar with that particular brand and never heard of it. Seems like a very expensive solution, at least in your case with the shipping. I checked to see if Jameson Lopp stress-tested this seed storage unit, but it's not on his list. If I wanted to use such a metal plate, I would check his review first to see how it survives the heat and corrosion tests. The manufacturer's promises and guarantees posted on the website are of secondary importance (or no importance at all).

Also, I don't like the space that was left for the 25th word, aka the passphrase. There isn't enough room. If your passphrase is the length of 6-8 random English words, for example, there is no way you will be able to engrave all that.

Coinplate Stainless Steel Seed Phrase Keeper
As I said in Fillippone's Washer  thread that I will post the thing which I will be using to keep my keys (seed phrase).


Where to keep seed phrase has been a thug of war in the mind of bitcoiners. Many questions Have been asked where to keep the keys (seed phrase). Coinplate steel is one of the best way or place bitcoiners can adopt to secure their bitcoin wallet keys (seed phrase).



In my locality, there is no store that has it, so I ordered it from online shipping which costed me $276.00 because of the distance of my country, that is excluding the shipping fees. The additional shipping fees of $50 was added and the total cost is $326.00.



The total size: 13.8 x 10.5 cm x 1 cm | 5.4″ x 4.1″ x 0.4″

The total weight: 1.14 kg | 2.5 lbs

The Plate size: 13.8 x 10.5 cm

 The Plate Thickness: 5mm | 3/16″

The Bolts diameter: 5mm | 3/16

The Material: 100% Stainless Steel, type: 1.4301 | AISI304, both plates and bolts

The Seed storage capacity: 24 words (2×12)


1. 2 stainless plates,
2. 2 stainless bolts
3. Automatic marking punch tool
4. Marker pen
5. Torx wrench for the bolts
6. Wood screws to fix Coinplate to furniture or elsewhere
7. Tamper evident security labels
8. Instruction manual





The coinplate is 100% stainless steel of (1.4301/AISI 304) which gurantees water and corrosion resistance. some even suggested paper wallet which can be washed away when wet. But coinplate is water proof



   It has been in the mind of bitcoiners or crypto users the best safest place to keep their keys. Coinplate steel is fire proof even if the temperature of the fire in house reach up to 8500 c /1.500 F. It will be still intact.




 Structure of the coinplate
The coinplate is made up of stainless steel joined with stainless bolts. each plate has 5mm l 3/16 thick.





  Finally:
wallet software genarate words and ask users to write them down in a safe place for future uses and most of the users use pen and paper to write it down and most time they lost the paper by misplacing it or tear it unknowingly, throw it away with other dirt or wet it water. Therefore coinplate steel is one of the best place to secure or safe your seed Phrase.
The seed Phrase is generated by the wallet software is called mnemonic.

 


https://getcoinplate.com

https://medium.com/coinmonks/how-to-secure-your-bitcoin-recovery-phrase-using-coinplate-steel-crypto-backup-255242e421b4