A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6685-00-135-4723
NSN 6240-01-086-3160
NSN 2925-01-517-4037
NSN 6685-01-123-1873
NSN 5935-01-537-0087
NSN 6240-00-405-5888
NSN 5930-00-291-5400
NSN 6240-00-326-2966
NSN 6135-00-840-6451
NSN 6610-01-421-4396
NSN 5999-01-521-3919
NSN 5930-00-315-3960