The JBO Thread Plug Gauge is a precision tool for verifying internal threads to the UNJF form. It's ideal for manufacturing, automotive, and aerospace quality teams that need fast, reliable hole checks on left-hand threaded components. Sized at 1/2 x 20 with a 3B tolerance, it provides a consistent reference for conformance during routine QC.

Built for daily use, the gauge features a robust, knurled body and a clear go/no-go design that makes it easy to identify conforming and non-conforming threads at a glance.

• UNJF form with 3B tolerance: Precisely machined to the UNJF thread form and 3B class, delivering a dependable reference for hole acceptance and reducing measurement guesswork.
• Left-hand thread compatibility: Specifically calibrated for left-hand threaded components, ensuring accurate checks without misreading standard right-hand gauges.
• Go/No-Go quick verification: Dual-ended design provides immediate pass/fail feedback, speeding inspections and helping maintain consistent thread quality across lots.

Using the JBO Thread Plug Gauge helps streamline your quality workflow by delivering clear, repeatable results every check. Inspectors save time with at-a-glance decisions, downtime is reduced from fewer reworks, and your team gains confidence that threaded holes will mate correctly in final assemblies. The rugged construction and precise dimensions stand up to busy shop environments, making this gauge a dependable part of your metrology toolkit.