+ 19% duty
Geez. If you were buying a few you'd be better off flying to China and bringing them home.
Which makes no difference if the amount is over Euro 400 if my memory serves me right (that's the free amount when bringing home stuff you bought on holidays). And German customs are notorious for finding hidden stuff in your suitcases and/or pockets. In best case, you make it through without any problems. In worst case, you end up being stuck at customs for hours filling in annoying forms, you pay the tax on site, and you wait for a court date and letter from the tax man with your penalty.
Much safer having ngzhang declare it as samples for a low value when using EMS, or take a hit on shipping time and use (registered) airmail which might slip through completely undetected if he writes "Adapter US$ 25" on the little green CN22 form.
With EMS it will be difficult to use such small value, because the shipping cost is already $35 and shipping is also added to the value for tax calculation. Customs are not stupid, they know product low value with shipping $35 is somehow fishy.
My recommendation: EMS use something like $100 and just pay up (19% of $100+$35 shipping). Don't mention the product name anywhere in the package or invoice (they use Internet to search for real prices). Include a proforma invoice that mentions "Development PCB". In worst case use a friends senders address/name (after finding one guy who got caught with a under-declared parcel from ngzhang they make a record in their database). However, they may ask the buyer for a copy of his bank records to see if the payment indeed matches the $100+$35 if they are suspicious. So if you are paranoid and you want to be on the safe side, send ngzhang two payments. Yes, German customs have a lot of time.
Airmail use "Adapter $25" or "Development PCB $25". No invoice needed. Will probably slip through undetected in most cases. It's tax free up until Euro 22. (US$ 25 = ~19 Euros). And for airmail there is no requirement for invoice, so they cannot ask. It's what I would do if I want to avoid the 19% at any cost.
Same for Austria and probably some other European countries.