A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5975-01-360-6105
NSN 5998-01-078-9797
NSN 5975-00-919-3715
NSN 6220-01-048-5584
NSN 5855-01-429-8702
NSN 5895-00-701-9458
NSN 5895-01-347-6940
NSN 5935-00-398-1584
NSN 5996-01-660-2811
NSN 5965-01-384-9923
NSN 6685-01-655-5146
NSN 6150-01-156-8264