Elliptical locking feature id
A soft metal or nonmetal sleeve, designed to mate with a pin-rivet. it may include an external wrenching facility which breaks off at a perdetermined torque to form a head.
NSN 5925-01-360-0110
NSN 5855-01-567-0096
NSN 5905-00-488-2793
NSN 5935-01-420-5687
NSN 5935-01-388-5531
NSN 6620-00-290-6505
NSN 5996-01-594-8747
NSN 5960-01-219-5504
NSN 5990-00-150-6979
NSN 5895-01-528-4280
NSN 6650-00-451-8174
NSN 5996-00-546-9486