A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5950-00-819-7299
NSN 5985-01-472-3658
NSN 6620-00-495-7438
NSN 5996-01-253-3486
NSN 5925-01-634-0664
NSN 5950-00-637-6131
NSN 6240-00-740-8901
NSN 6610-01-321-6904
NSN 5965-01-661-0996
NSN 4140-01-110-1980
NSN 5990-01-481-3080
NSN 5910-01-143-2235