A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6320-01-462-3555
NSN 6110-00-727-1377
NSN 6105-00-508-1239
NSN 5975-00-539-7300
NSN 5960-01-120-2170
NSN 5998-01-136-7881
NSN 7035-01-359-6108
NSN 6240-01-415-5581
NSN 2925-01-196-6187
NSN 6645-00-819-5045
NSN 6685-01-631-4225
NSN 5950-00-518-4645