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 6610-01-242-9674
NSN 6110-01-288-7996
NSN 6105-00-389-4632
NSN 5920-00-336-9055
NSN 5835-00-583-1316
NSN 6650-01-421-5355
NSN 5910-01-280-3201
NSN 5935-01-503-7491
NSN 6320-01-445-5893
NSN 6220-01-238-1609
NSN 5996-01-473-2183
NSN 6320-00-925-0558