A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5996-01-660-9986
NSN 6645-00-296-8310
NSN 5975-01-332-6909
NSN 5975-01-147-3011
NSN 5985-01-140-9479
NSN 6130-00-403-1439
NSN 5990-01-584-8363
NSN 5985-01-098-7598
NSN 5985-01-421-1721
NSN 6650-00-161-4122
NSN 6320-01-415-0953
NSN 6130-00-165-6365