A headless fastener externally threaded on both ends with each threaded portion of one but not necessarily the same nominal diameter. It is designed to be locked in place by either a ring, lock, serrated or a ring, lock, keyed.
NSN 5925-01-301-6698
NSN 5930-01-521-8379
NSN 6320-01-631-7828
NSN 5996-01-340-8813
NSN 5965-01-386-2988
NSN 6620-00-730-8699
NSN 6220-00-635-8818
NSN 4140-01-062-7244
NSN 5915-00-369-7890
NSN 6145-01-384-6003
NSN 5999-01-350-8656
NSN 5855-00-135-9064