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 6145-01-458-0972
NSN 5985-01-168-8313
NSN 5855-01-631-5051
NSN 5998-01-533-4793
NSN 5930-01-611-1977
NSN 6150-01-533-2874
NSN 6685-00-797-7543
NSN 5835-00-264-0946
NSN 6220-01-575-6023
NSN 4140-01-172-4637
NSN 6105-01-463-8557
NSN 6320-00-845-3261