A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5905-01-142-8665
NSN 5985-01-203-4883
NSN 5930-00-124-5170
NSN 6610-01-398-8092
NSN 5835-00-280-8494
NSN 5945-01-408-5977
NSN 5965-01-380-5875
NSN 4140-01-463-9299
NSN 5905-00-675-9552
NSN 5960-00-250-7942
NSN 5910-01-088-6848
NSN 5985-01-589-6920