A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6620-01-367-4960
NSN 2925-00-497-7808
NSN 7035-00-349-8571
NSN 6135-00-284-1406
NSN 5945-00-445-6362
NSN 5925-01-192-1452
NSN 6220-01-600-5971
NSN 6650-01-235-7555
NSN 6685-00-260-5628
NSN 5960-00-129-6660
NSN 5945-01-631-9954
NSN 5998-01-286-1160