I bought this a few years ago, but I never used it and just stored it. There might be some creases, so those who are concerned might notice them. Product Description: Sacoche made of Tyvek®. Tyvek® is also used for the name tags of previous sacoches. The material used for the tags is the soft type, but this time the hard type is used. Tyvek® is a high-density polyethylene nonwoven fabric uniquely developed by DuPont. It is a sheet (nonwoven fabric) made by randomly layering extremely fine, 0.5-10 micron polyethylene long fibers and bonding them only with heat and pressure. This unique structure, developed by DuPont in the United States, provides excellent moisture permeability and waterproof performance, as well as outstanding strength and durability.