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 6610-01-529-5709
NSN 6130-01-381-9473
NSN 5855-00-149-0766
NSN 4140-00-995-3268
NSN 6130-00-297-5793
NSN 6145-01-415-3978
NSN 5950-01-569-3353
NSN 2925-01-446-6523
NSN 6220-00-140-4158
NSN 6145-01-484-3567
NSN 6135-00-686-4777
NSN 5925-00-240-7676