The JBO Thread Plug Gauge is a precision tool engineered for metric fine threads. Designed for internal hole checks, it helps engineers, machinists, quality control professionals, and workshop hobbyists quickly verify that threads meet exact size and tolerance before assembly. Its Go/No-Go design provides fast, reliable pass/fail results, so you can move parts through your workflow with confidence.

• Go/No-Go design: Enables fast, repeatable inspections of threaded holes, reducing guesswork and speeding up quality checks.
• Hardened steel construction: Built to withstand daily use in demanding environments, delivering long service life and maintained accuracy over time.
• Metric fine thread focus (M3.5 x 0.25, 6H, Right-Hand): Specifically calibrated for fine metric threads with a standard right-hand orientation, ensuring reliable checks that align with common production standards.

Using this gauge streamlines your inspection process, helps prevent mismatches during assembly, and supports consistent results across batches. The durable build and precise Go/No-Go checks give you dependable performance, enabling faster turnarounds, reduced rework, and increased confidence in every measurement.