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 5910-00-266-8438
NSN 5905-00-408-6668
NSN 5985-01-423-1057
NSN 5920-01-263-9259
NSN 6320-00-382-7825
NSN 6220-00-493-8957
NSN 5999-01-194-0005
NSN 4140-01-542-4701
NSN 5999-00-824-7917
NSN 6105-00-328-0793
NSN 5920-00-981-5803
NSN 5835-01-584-8538