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 5996-01-569-2392
NSN 5915-00-959-5454
NSN 6645-00-527-7258
NSN 6105-00-831-6113
NSN 6240-01-575-8590
NSN 5985-00-189-0599
NSN 6650-01-295-7896
NSN 5915-01-583-9732
NSN 5935-00-554-0244
NSN 6620-01-495-7446
NSN 5999-01-399-7849
NSN 5985-00-540-1964