The JBO Thread Plug Gauge is a precision Go/No-Go probe designed for metric fine threads. It targets M5 x 0.5 with a 4H hole tolerance and is right-hand oriented for common production fits. Built for quick, reliable checks, it helps ensure threaded holes accept components consistently.

Designed for engineers, machinists, QA inspectors, and workshop hobbyists, this gauge provides fast, clear pass/fail feedback so you can confirm thread size and tolerance at a glance—without guesswork or trial assemblies.

• Go/No-Go design for quick verification: Quickly confirm hole size and thread fit using the go and no-go ends, reducing inspection time and preventing under- or over-tolerance assemblies.
• Precise metric fine thread compatibility: Specifically engineered for M5 x 0.5 fine threads in 4H tolerance, ensuring accurate checks for critical components.
• Hardened steel for lasting durability: Built from durable hardened steel to resist wear and maintain accurate measurements through heavy use in busy workshops.

With this gauge, you can speed up setup and inspections, reduce rework, and improve overall threading quality across parts. The Go/No-Go design provides decisive results, while the hardened steel construction keeps tolerances stable for reliable performance over time.