Ground terminal accepts wires up to 8 AWG, other terminals up to 10 AWG. Cable protectors are constructed of plated steel, and provide strain relief and protection against abrasion. Cole Hersee spring grip contacts contain a self-adjusting spring band that maintains contact pressure from socket to pin. Greater contact pressure not only gives greater electrical efficiency, but also makes coupling and uncoupling uniform, and minimizes buildup of dirt. In competitive plugs, conventional contacts tend to widen after repeated use: the Cole Hersee plug has individually sprung sockets to insure maximum contact year after year. Die-cast metal housing. Replaceable interior. Wiring codes are identified on the insulator. Cable clamp holds all wires securely.