This cap nut is made of nylon with a natural color surface treatment, following the GB standard. It features a round head and internal metric thread with a blind hole, designed to cover threaded ends and protect them from rust, dirt, and damage. The nut also reduces the risk of injury from sharp screw ends. It is compatible with all standard screws, including cylindrical, round head, countersunk, hex, and other machine screws. Suitable for use in dry, damp, and outdoor environments, this nut is ideal for applications in mechanical industry, automobile and motorcycle manufacturing, wooden and steel structures, and furniture construction.