A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6240-00-340-6977
NSN 6320-01-343-8191
NSN 6135-01-168-2944
NSN 5950-01-209-4710
NSN 5910-00-006-1498
NSN 6320-01-450-7513
NSN 5935-00-670-7895
NSN 5905-00-401-7430
NSN 5935-00-135-0771
NSN 5985-01-100-1206
NSN 6320-01-328-6575
NSN 2925-00-174-4322