A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5895-01-633-0983
NSN 5855-00-237-4088
NSN 6145-01-449-7937
NSN 5930-01-519-9105
NSN 6645-01-510-3496
NSN 2925-01-167-6500
NSN 5990-01-324-1204
NSN 5945-01-180-9740
NSN 6645-01-330-6028
NSN 5999-01-173-9031
NSN 6620-01-274-3423
NSN 5930-00-762-9131