A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5990-00-067-6545
NSN 6135-01-551-0562
NSN 5835-00-034-4976
NSN 5990-01-278-9985
NSN 6645-01-166-3788
NSN 5950-01-184-9395
NSN 6645-01-550-9669
NSN 6645-00-871-1187
NSN 5960-01-389-4055
NSN 6620-00-475-9985
NSN 5935-00-097-3970
NSN 6110-01-468-4801