The JBO Thread Plug Gauge is a precision inspection tool for metric coarse threads. This left-hand Go/No-Go gauge is calibrated for M36 x 4 holes, allowing fast, consistent verification of thread fit during assembly, machining checks, and quality control.

Made from hardened steel, it is built to endure daily use in demanding shop environments, resisting wear that could affect accuracy. The compact, knurled body provides a secure grip for quick insertions and reliable readings.

• Go/No-Go quick verification: The single-insertion check quickly confirms whether the hole meets the required M36 x 4 thread tolerance, reducing inspection time and rework.
• Hardened steel construction: With hardened steel, the gauge resists wear from repeated use and maintains accuracy for long service life in busy workshops.
• Left-hand, metric coarse accuracy (M36 x 4, 6H): Specifically calibrated for left-hand coarse threads to ensure correct engagement and consistent results, supporting reliable assembly of left-handed components.

Using this gauge helps speed up quality checks, minimize downtime, and ensure that every threaded hole will accept the intended fastener, delivering consistent, reliable performance in your manufacturing or maintenance tasks.