The JBO Thread Ring Gauge (GO) for UNC Left Hand, 2A, No. 12 x 24 is a precision measurement tool designed to quickly and reliably verify external thread diameters. It’s ideal for engineers, inspectors, machinists, and workshop technicians who need fast, confident go/no-go checks against UNC specifications.

Crafted from hardened steel, this gauge resists wear and maintains accurate tolerances in demanding environments. Its GO design makes it easy to identify properly conforming threads at a glance, streamlining quality control and precision engineering workflows.

• Precise GO gauge for UNC Left-Hand threads: Delivers quick pass/fail verification against the GO limit, helping ensure components meet UNC specifications with reliable, repeatable results.
• Hardened steel construction: Built to endure daily use in busy shops, providing long-lasting durability and sustained accuracy even after repeated insertions and removals.
• User-friendly conformance checks: Clear, straightforward checks that speed up inspections and reduce downtime, making quality control more efficient for teams of any skill level.

By delivering clear measurements for external UNC threads, this GO ring gauge supports faster inspections, consistent part quality, and smoother assembly processes. It helps you verify compliance with standards, cut down rework, and maintain reliable performance across demanding manufacturing, maintenance, and engineering workflows.