MS21042-5 All-Metal Self-Locking Nut | 5/16-24 Aircraft Lock Nut

MS21042-5 All-Metal Self-Locking Nut

The MS21042-5 is an all-metal self-locking aircraft nut, also known as an All-Metal Stop Nut or Self-Locking Nut. It is used in aircraft applications where nylon-insert nuts are not recommended, especially in areas subject to elevated temperatures.

The nut features a 5/16-24 UNJF thread, low-profile design, and all-metal construction, making it shorter than the AN363 nut while maintaining similar locking functionality. The MS21042 family is designed for high-temperature installations, typically up to 450°F, and is manufactured from carbon steel with cadmium plating.