A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5910-00-823-6310
NSN 6130-01-259-1615
NSN 5960-00-021-5618
NSN 5915-01-352-6836
NSN 6105-00-596-9962
NSN 5945-00-915-5685
NSN 6620-00-098-5652
NSN 6610-00-960-1561
NSN 5920-01-146-3603
NSN 5998-00-422-4619
NSN 5935-01-264-8956
NSN 6320-00-149-7570