A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 2925-01-347-4208
NSN 6685-01-114-4878
NSN 6620-00-800-5579
NSN 6320-00-194-4252
NSN 5835-01-436-6549
NSN 6135-01-648-4875
NSN 6110-01-050-9490
NSN 5975-00-902-8238
NSN 5945-01-625-3747
NSN 6145-01-474-5230
NSN 6130-00-352-2317
NSN 5999-00-909-8808