A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5975-00-269-8391
NSN 6685-01-470-2017
NSN 5935-01-628-4373
NSN 6620-01-449-8743
NSN 2925-01-194-9737
NSN 6130-00-943-1810
NSN 5905-00-389-3293
NSN 5895-01-378-7088
NSN 5960-01-285-2152
NSN 5999-00-683-6660
NSN 5945-01-333-0310
NSN 5998-00-245-1973