A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5905-01-490-2295
NSN 6220-01-371-1058
NSN 5905-01-444-4857
NSN 6105-01-634-0322
NSN 5855-00-256-5562
NSN 6135-01-531-1413
NSN 7035-00-782-7046
NSN 5998-00-233-0883
NSN 5855-01-504-4750
NSN 5965-00-564-4399
NSN 5985-01-069-2886
NSN 5998-01-429-9425