This all-metal self-locking hex nut, also known as a lock nut, features a built-in locking mechanism that helps prevent it from working loose under vibration or mechanical stress. Made from steel with an electro-galvanized, yellow-passivated finish, it's designed for indoor use or applications with very mild exposure. Rated at strength class 6, this nut pairs well with bolts and screws up to grade 6.8. It comes with standard metric threading.