A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5960-01-135-9238
NSN 6145-00-866-0957
NSN 6645-00-371-1861
NSN 6320-01-384-3850
NSN 2925-01-157-9204
NSN 5996-01-417-8669
NSN 6105-01-386-4038
NSN 5910-00-289-5638
NSN 5996-01-594-6798
NSN 5960-01-223-6202
NSN 5895-00-177-7924
NSN 5998-01-472-2520