A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5910-01-347-0260
NSN 6610-00-323-8175
NSN 6220-01-388-2624
NSN 6130-00-435-9473
NSN 5920-00-140-1492
NSN 6240-01-381-2275
NSN 5945-01-327-2697
NSN 5960-01-309-1280
NSN 5998-01-021-5665
NSN 6645-00-074-4580
NSN 5945-00-428-6353
NSN 6620-01-473-5163