A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6645-00-216-6126
NSN 5895-01-252-5885
NSN 5945-00-652-0639
NSN 5985-01-385-5294
NSN 5895-01-012-8780
NSN 5999-00-816-9670
NSN 5935-00-393-8219
NSN 5935-00-690-5197
NSN 6130-01-511-9616
NSN 5920-01-142-1836
NSN 6645-01-462-2101
NSN 5920-01-083-3749