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 5930-01-525-1182
NSN 6150-00-233-5833
NSN 6320-01-567-9792
NSN 6645-01-312-8601
NSN 5960-01-512-0233
NSN 6145-00-360-7760
NSN 5999-01-332-2879
NSN 6610-01-074-8158
NSN 6240-00-432-1320
NSN 5945-01-472-8713
NSN 5990-01-605-4769
NSN 6220-01-077-9868