The JBO Thread Ring Gauge (GO) – Metric Coarse – Left Hand – 6e – M20 x 2.5 is a precision inspection tool designed to verify external metric threads. Ideal for quality control teams, machine shops, and maintenance crews, it helps ensure metric coarse left-hand connections meet the correct diameter so assemblies thread smoothly the first time.

Manufactured from hardened steel, this GO gauge delivers dependable durability and wear resistance for repeated use in busy work environments. Its compact, easy-to-handle design supports quick, accurate go/no-go checks, helping inspectors confirm fit and function without guesswork.

• GO gauge for metric coarse left-hand threads: Quickly verify that M20 x 2.5 left-hand threads meet the required diameter, enabling reliable mating and reducing assembly issues.
• Hardened steel construction: Built to endure daily inspection cycles with minimal wear, preserving accuracy over thousands of measurements.
• Precise 6e tolerance: Maintains consistent, repeatable results across production runs, supporting standard compliance and reducing rework.

Used in quality control workflows, this gauge streamlines inspections, shortens downtime, and gives you confidence that threaded components will fit correctly in critical applications—from machinery assemblies to maintenance replacements.