A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5990-01-443-2931
NSN 6130-01-160-7772
NSN 5935-00-089-2167
NSN 5990-00-503-4724
NSN 5975-00-903-2284
NSN 5996-01-075-8467
NSN 5895-01-227-5213
NSN 6610-00-875-1724
NSN 2925-01-642-3255
NSN 6135-01-069-2482
NSN 6240-01-407-5690
NSN 5925-01-107-6471