A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6130-01-180-3176
NSN 5925-01-624-8671
NSN 5915-00-992-6406
NSN 6650-01-106-8601
NSN 6645-01-141-7016
NSN 6150-01-314-6062
NSN 2925-01-575-1505
NSN 5910-00-312-2631
NSN 6610-01-038-6780
NSN 6320-01-029-4220
NSN 5910-01-454-9298
NSN 6105-00-809-4356