A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5915-00-353-0853
NSN 6105-01-224-0549
NSN 2925-00-964-7128
NSN 6650-01-144-5351
NSN 6620-00-451-6189
NSN 5930-01-327-9645
NSN 5930-00-840-9991
NSN 5835-01-473-6187
NSN 5920-01-321-4327
NSN 5985-01-526-9271
NSN 6610-01-445-7120
NSN 5945-01-163-8683