A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5975-00-279-3972
NSN 6135-00-985-7887
NSN 6240-00-776-1614
NSN 5930-00-889-1300
NSN 6110-01-453-9302
NSN 4140-01-152-6600
NSN 6320-00-360-1744
NSN 5999-01-121-9080
NSN 5920-01-363-1426
NSN 5915-01-509-1941
NSN 5985-01-571-0009
NSN 5965-01-426-5283