A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6620-00-932-6508
NSN 5950-01-174-1725
NSN 5945-00-711-1814
NSN 5950-01-185-9923
NSN 6105-01-233-6951
NSN 6145-01-055-4699
NSN 6135-01-214-6441
NSN 4140-00-960-8222
NSN 5835-01-310-8979
NSN 5985-01-595-9942
NSN 7035-00-574-4223
NSN 6645-01-511-3272