Size number 4, split lock washer
No other part numbers with same form, fit, and function found.
A washer which is usually round with a centrally located hole. Its edges and two bearing surfaces are so designed that applied pressure brings into play the spring tension and/or frictional locking principle which materially resists any tendency toward turning. It may be made of one or two pieces
NSN 5990-01-160-6978
NSN 5965-01-503-0699
NSN 5975-00-223-1853
NSN 5855-01-459-9254
NSN 6135-00-080-9176
NSN 5930-00-507-2220
NSN 5985-01-459-8218
NSN 6135-01-141-4916
NSN 6320-01-481-7322
NSN 6685-00-411-5496
NSN 5910-01-510-1919
NSN 5965-00-113-9748