The JBO Thread Plug Gauge is a Go/No-Go inspection tool designed for metric fine threads. It’s ideal for machinists, inspectors, engineers, and maintenance technicians who need fast, reliable thread verification to ensure parts fit correctly before assembly. The knurled grip provides a secure, comfortable hold for precise checks in busy workspaces.

Designed for M4 x 0.5 fine threads with a right-hand orientation and 6H tolerance, this gauge delivers accurate checks in a compact, durable package. Its hardened steel construction resists wear, delivering long-lasting performance even with frequent use.

• Go/No-Go speed checks: Quickly confirm whether an internal thread meets size and pitch tolerances, reducing inspection time and guesswork.
• Durable hardened steel construction: Built to withstand daily use, resisting wear to maintain consistent accuracy over time.
• Metric fine thread compatibility: M4 x 0.5, Right Hand: Precisely sized for common metric threads and standard hole orientations, enabling reliable results across typical applications.

Using the JBO Thread Plug Gauge helps you streamline quality control, ensure correct thread engagement before assembly, and maintain consistent performance across parts and assemblies. It supports faster workflows, reduces rework, and gives you confidence in your threaded connections from first article through final product.