Hex-head plug

A hex-head plug is a forged threaded component that closes a threaded opening and provides an external hexagonal tool-engagement head. Its primary distinction from a square-head plug is the tool-interface geometry; no performance, allowable-torque, or removal advantage follows without product data. The generic title does not define thread form, solid or cored body construction, material, or class. Selection should specify the male and mating threads, sealing method, wrench clearance for the hex head, material, service conditions, and safe removal procedure for maintenance.