A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5935-01-147-2359
NSN 6645-00-953-4170
NSN 6220-00-843-1441
NSN 6240-01-142-8923
NSN 6145-00-815-1388
NSN 5910-00-109-4852
NSN 5855-01-162-5251
NSN 6150-01-607-5915
NSN 5935-01-554-7195
NSN 6620-01-449-8743
NSN 5930-00-106-7222
NSN 5855-00-763-2155