Hex nipple

A hex nipple is a short threaded connector with a central hexagonal wrenching section for assembly and removal. This tool-engagement geometry distinguishes it from a tubular pipe nipple without a central hex body and from a bushing that provides an external-to-internal connection relationship. The title alone does not establish equal or reducing end sizes, thread form, material, or coating, and the Persian term may be used more broadly in trade. Selection should define both end arrangements and sizes, wrench clearance, sealing method, thread engagement, and future disassembly needs.