A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6150-00-141-8793
NSN 6105-00-617-8648
NSN 5835-01-616-6131
NSN 5960-01-577-5682
NSN 2925-00-328-5204
NSN 6320-01-052-2118
NSN 2925-01-094-4771
NSN 6650-01-188-8028
NSN 5985-00-088-0695
NSN 6130-01-455-4497
NSN 6620-00-467-7414
NSN 5998-01-422-4196