Vulcanized fibre is a laminated plastic composed of only cellulose. The material is a tough, resilient, hornlike material that is lighter than aluminium, tougher than leather, and stiffer than most thermoplastics.
Commercial Grade; standard grey, black or red, used for many applications such as washers, gaskets, gears, handles, etc.
A product very similar to vulcanized fibre is leatheroid. Leatheroid, however, is made using a different chemical process.