A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5835-01-381-9565
NSN 5835-01-386-4027
NSN 6110-00-618-4171
NSN 5950-00-106-2026
NSN 5925-01-344-8932
NSN 4140-01-506-2479
NSN 6240-01-615-0357
NSN 5930-00-153-1400
NSN 5925-01-431-8886
NSN 5985-01-619-4116
NSN 5915-00-823-8334
NSN 5930-01-406-4281