The JBO Thread Plug Gauge is a Go/No-Go inspection tool calibrated specifically for metric coarse threads. It’s ideal for engineers, machinists, quality teams, and even advanced hobbyists who need to verify threaded holes quickly and confidently, ensuring that parts fit precisely and function as intended.

Designed for M20 x 2.5 coarse-thread holes, this gauge features right-hand orientation and a 4H tolerance to align with standard components. Crafted from hardened steel, it stands up to busy workshop use while maintaining long-lasting accuracy. The knurled body provides a secure, comfortable grip for precise handling in any environment.

• Go/No-Go inspection design: Quickly confirm whether a threaded hole passes or fails against tight tolerance limits, reducing guesswork and speeding up quality checks.
• M20 x 2.5 coarse-thread ready: Precisely sized for common metric coarse threads, ensuring reliable fitment with standard bolts and components.
• Hardened steel construction with secure grip: Built for durability and consistent accuracy in demanding settings, with a knurled surface that stays steady even with gloves on.

This gauge streamlines your workflow by delivering clear, pass/fail results in seconds, helping you prevent misfits, cut rework, and shorten inspection cycles. Its rugged construction and thoughtful design mean you can rely on it day after day to verify thread readiness, improve assembly reliability, and support consistent quality across projects and batches.