A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5915-01-513-9122
NSN 6620-01-443-3526
NSN 6110-00-282-8562
NSN 6320-01-395-9148
NSN 5945-01-503-4613
NSN 6620-01-441-7896
NSN 6220-00-348-2411
NSN 6610-01-518-3044
NSN 5945-00-363-9481
NSN 5985-01-318-0410
NSN 5950-00-971-8993
NSN 6220-01-441-0977