A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 7035-00-922-5700
NSN 5905-01-050-1827
NSN 5930-01-406-6293
NSN 5835-00-603-8477
NSN 5975-01-216-2705
NSN 5935-01-529-6191
NSN 5965-00-445-1843
NSN 5996-01-443-8755
NSN 5895-01-564-0534
NSN 6240-01-594-5703
NSN 5960-01-374-3527
NSN 2925-01-446-0525