The JBO Thread Ring Gauge (GO) for UNEF left-hand threads (7/8 x 20, 2A class) is a precision inspection tool designed to quickly and reliably verify external thread diameters. It helps manufacturers, machinists, quality-control teams, and maintenance technicians confirm that UNEF 7/8 x 20 left-hand components meet the GO size and tolerance requirements.

Crafted for durability in demanding environments, this ring gauge uses hardened steel construction with a wear-resistant finish to maintain accuracy over many cycles. Its simple, unobstructed ring design makes it easy to slip over the threads and perform a clear go/no-go check in seconds.

• Accurate UNEF GO sizing: Designed to precisely match the GO limit for UNEF 7/8 x 20 left-hand threads, enabling fast, reliable pass/fail checks on production lines and in inspection benches.
• Hardened steel construction: High-grade material with a wear-resistant finish that withstands repeated use in tough shop environments, delivering long service life and consistent results.
• User-friendly inspection tool: Easy to use—slip over the thread to confirm conformance quickly, helping reduce downtime and minimize misfits in assemblies.

This GO ring gauge helps you maintain tight quality control by delivering clear, pass-or-fail results on each part. By speeding up inspections, it reduces the need for rework, keeps production moving, and ensures mating components align with UNEF standards every time. With its robust steel construction and precise sizing, you can rely on consistent measurements across shifts, tools, and operators, boosting confidence in your threaded assemblies and overall workmanship.