A lock nut is a type of nut that is used to secure a bolt or other threaded fastener. The lock nut has a series of internal threads that mate with the external threads of the bolt or fastener. The lock nut also has a series of locking elements, such as teeth or splines, that engage with the threads of the bolt or fastener. When the locknut is tightened, the locking elements prevent the nut from loosening. Lock nuts are used in a variety of applications, such as automotive and aerospace assemblies.The most common type of lock nut is the square bng bngs bnr bnrs locknut. This style of locknut has four sides that are equally spaced around the circumference of the nut. The four sides give the square bng bngs bnr bnrs locknut greater torque-bearing capacity than a standard hexagonal nut. The square shape also allows the nut to be seated more securely in a countersunk hole.