A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5855-01-417-3250
NSN 6320-01-554-0901
NSN 6620-01-633-7058
NSN 5910-01-219-1806
NSN 5925-01-306-4454
NSN 6645-00-810-7229
NSN 6685-01-474-4460
NSN 6130-01-358-4064
NSN 5915-01-448-9399
NSN 6685-01-342-8985
NSN 5985-00-715-4015
NSN 5945-01-201-1416