Zytel - Zytel is a trademark owned by DuPont and used for a number of different high strength, abrasion and impact resistant thermoplastic polyamide formulations of the family more commonly known as nylon, often with varying degrees of fiberglass, from 13% to 60%, added in for additional stiffness. Some of the grades are homopolymer nylon 66, other copolymers with nylon 6 repeat units, and further grades involving rubber toughening are available.