The JBO Thread Plug Gauge (GO) – Metric Fine, Right Hand, 6H, M138 x 1.5 is a precision go gauge designed to verify internal threads in a wide range of components and assemblies. It helps machinists, inspectors, and quality teams quickly confirm that threaded holes meet the exact size and class required for reliable assembly.

Designed for durability and repeatable results, this GO gauge delivers fast, confident checks on threaded holes, supporting consistent production outcomes and quality control workflows.

• Durable hardened steel construction: Built to withstand the demands of busy shops, providing long tool life and sustained accuracy through thousands of inspections.
• Precise metric fine GO specification: M138 x 1.5 with 6H tolerance delivers consistent, repeatable checks across batches, reducing guesswork during quality control.
• Ergonomic, user-friendly design: Knurled body and clean seating surface enable fast orientation and easy GO checks, minimizing inspection time and confusion on the shop floor.

With the JBO Thread Plug Gauge, you gain faster, more reliable quality control. It helps you identify correctly threaded holes in seconds, reduces rework, and supports consistent assembly tolerances. Its sturdy construction keeps its accuracy over many cycles, making it a trusted choice for production lines, workshop benches, and engineering labs.