The item is a flight safety critical aircraft part (fscap)
A nut having 6 flat sides and an integral washer which extends beyond the flats or periphery. An integral feature is incorporated for locking on the threads of a mating member.
Classification: Nuts of iron or steel
NSN 6105-00-202-2469
NSN 6110-01-027-1172
NSN 5935-01-153-2662
NSN 6685-00-251-1366
NSN 5920-00-644-0379
NSN 5999-01-617-6665
NSN 5915-00-764-8686
NSN 5945-01-578-0924
NSN 6145-01-422-5319
NSN 6240-01-268-2223
NSN 5930-01-446-9240
NSN 5835-01-522-9881