A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5996-01-541-4974
NSN 5998-01-363-3259
NSN 6145-00-818-8679
NSN 5930-01-570-2292
NSN 5975-01-644-3155
NSN 5895-01-242-8097
NSN 6685-01-376-9836
NSN 7035-01-235-6023
NSN 5925-01-430-5306
NSN 6650-01-529-4601
NSN 6320-01-462-3555
NSN 5998-00-445-1524