A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6645-00-498-6869
NSN 5835-01-442-6482
NSN 5945-01-495-5526
NSN 5996-01-247-4407
NSN 5895-01-106-7330
NSN 5998-01-198-1300
NSN 5965-00-267-4173
NSN 5925-00-412-5342
NSN 5905-01-159-2636
NSN 6135-01-472-9011
NSN 6110-00-185-2021
NSN 6685-01-035-2167