Nylon Nut

A Nylon insert lock nut, polymer insert lock nut, is a kind of nut that includes a nylon collar insert. The insert is placed at the end of the nut and its inner diameter (ID) is slightly smaller than the major diameter of the screw. The insert deforms elastically over the threads of the screw, but threads are not cut into the nylon. The nylon insert locks the nut in two ways. First, it forces the bottom face of the screw threads against the top face of the nut threads, increasing the friction between the two. Second, the nylon applies a compressive force against the screw itself. Nyloc nuts retain their locking ability up to 250 OF (121 OC).