Stainless steel nylon lock nuts, also referred to as nylon insert lock nuts, are hexagonal threaded fasteners fitted with a built-in nylon ring at the top. The nylon insert creates friction against bolt threads to resist loosening caused by vibration.
Made from 304 or 316 stainless steel, these nuts combine corrosion resistance with reliable self-locking performance. When tightened, the nylon ring deforms slightly around the bolt thread, generating constant friction to prevent unintended loosening. They are reusable for limited times and widely applied in machinery, automotive, rail equipment and outdoor installations where vibration and shock exist.