It is polymer which has average values between the vulcanized rubbers and thermolayers (PP, PE and other). TPU consist of air (simple and difficult) and diols (diisocyanates).
It is necessary to allocate that in TPU there are no softeners in structure. Nevertheless, for special applications there are brands containing softeners. But if it is necessary specific properties, then for this purpose there are brands with softener.
Hardness of brands varies from 60 on Shora of A to 75 according to Shor D.
Important feature is lack of softeners in a compounding. Nevertheless, for special applications there are brands containing softeners.