A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6220-01-087-7755
NSN 6610-01-512-2025
NSN 5930-01-168-8069
NSN 6110-00-271-9928
NSN 6145-00-199-5093
NSN 5960-00-153-4669
NSN 6150-00-147-3680
NSN 6135-00-248-4102
NSN 6240-00-981-8218
NSN 6320-00-831-2227
NSN 2925-01-083-3986
NSN 6145-00-145-8573