Do you have any idea how are they able to provide this profitability? In essence, this is mining without fees?
Well, they do manufacture their own hardware so they are getting the best possible price there; and essentially you are leasing the miner for, say 200 days or so and they keep the rig. The main advantage to them is they ROI as soon as you pay your contract and in return they pay you a small premium near the end of the contract.
Think of it like a bond, or a loan. Conceivably they can take your money today and use it to make more rigs, more quickly (and make more profit) than if they mined for themselves.