Drift diameter gauges are simple and general tool designed to measure inside drift size of casing, tubing,drill pipe and other pipes. In order to live up to the standard requested, it used to inspect the inside drift size of a variety of tubings. The biggest size will be known through inspecting after deformation. It is the essential tool in the course of work over . Features: Drift Diameter Gauges are simple in structure, safe and reliable in use, high-efficiency performance, convenience operation.