A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6220-00-594-8817
NSN 6320-01-159-2211
NSN 6145-01-272-5753
NSN 6220-00-842-2483
NSN 5915-00-153-0002
NSN 6645-00-476-7176
NSN 5855-01-195-2518
NSN 5975-01-576-1086
NSN 6685-01-105-1356
NSN 6145-01-474-1115
NSN 6620-00-532-2068
NSN 6110-01-444-3302