A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6320-01-532-7491
NSN 5990-00-212-4316
NSN 5930-00-792-1551
NSN 6320-01-384-3850
NSN 5935-00-737-1268
NSN 7035-00-511-0076
NSN 5950-00-517-0467
NSN 6110-01-069-4895
NSN 5985-00-807-3021
NSN 5945-00-519-6529
NSN 5920-00-391-6252
NSN 5999-00-423-3514