The JBO Thread Plug Gauge (GO) is a precision inspection tool designed to verify metric coarse internal threads. Built for machinists, quality control professionals, engineers, and maintenance teams, it provides a simple, reliable pass/fail check to ensure holes meet the M42 x 4.5 standard with a 6H tolerance. Designed for use in busy workshops, it helps you confirm thread quality quickly and with confidence.

• Metric coarse thread GO gauge for M42 x 4.5: Enables fast, decisive verification of threaded holes, supporting accurate assembly and reducing rework by confirming compliance with the standard.
• Hardened steel body with knurled grip: Durable, wear‑resistant construction that stands up to daily use in demanding environments and provides a secure, comfortable grip even with gloves on.
• Right‑hand design with 6H tolerance: Ensures consistent, repeatable measurements across parts and setups, aligning with common metric coarse thread standards for dependable quality control.

Using this GO gauge helps you streamline quality checks, speed up production workflows, and ensure threaded connections fit as intended. Its robust construction minimizes downtime and replacement costs while delivering reliable, repeatable results that you can trust in both manufacturing and maintenance contexts.