Extremely stiff--top layer not made of waterproof material
This cap is extremely still and uncomfortable to wear.  Elastic is also not sewn well, so the elastic rim pokes you all around.  The outer layer is a silky, porous material that soaks up water and doesn't repel it.  Your hair stays dry with this cap, but I'd imagine there's a very real possibility of mold growing between the cap's two layers.  I definitely wouldn't buy again.
Rating: 2 stars