JBO Thread Plug Gauge - Metric Coarse Go/No-Go - Left Hand - 5H - M1.2 x 0.25 Hex Key Drill Chuck Built to BS 328/4 taper

Built to BS 328/4 taper shank standards in standard length

repeatable results that translate to higher first-pass success

A 10-micron run-out specification helps keep your tools centered during high-speed operation

With a broad range of specifications—different sizes

delivering consistent concentricity across milling and drilling operations

JBO Thread Plug Gauge - Metric Coarse Go/No-Go - Left Hand - 5H - M1.2 x 0.25 Hex Key Drill Chuck Built to BS 328/4 taperThe JBO Thread Plug Gauge is a precision Go No Go tool designed specifically for metric coarse threads. Its ideal for engineers, machinists, quality teams, and shop technicians who need fast, reliable verification that threaded holes meet spec for proper fit and function. This left hand version is sized for M1. 2 x 0. 25 with a 5H tolerance, helping you confirm correct engagement in assemblies that use left handed threads. Go No Go verification for