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 6650-01-076-3449
NSN 2925-00-411-6324
NSN 4140-00-163-2868
NSN 7035-01-485-2134
NSN 5905-00-327-9689
NSN 5925-00-026-1977
NSN 5950-01-517-5112
NSN 5960-01-214-0951
NSN 5925-00-632-6098
NSN 6220-01-457-9097
NSN 6110-01-436-1006
NSN 5945-00-639-0646