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 5905-01-463-7326
NSN 6220-01-358-0365
NSN 5965-00-680-9749
NSN 5925-01-494-3760
NSN 5905-01-603-5544
NSN 5925-01-469-6068
NSN 5965-01-399-8454
NSN 6685-01-486-6410
NSN 5920-01-350-2282
NSN 5895-00-188-6798
NSN 5965-00-841-9195
NSN 7035-01-633-9204