The JBO UNC Go-No/Go Thread Plug Gauge is a precision inspection tool designed to verify 1/2 x 13 Unified National Coarse (UNC) threads in holes and threaded bores. It’s ideal for engineers, machinists, quality teams, and shop-floor technicians across manufacturing, automotive, and aerospace who need fast, dependable thread checks.

With its go/no-go design and a 2B tolerance class, this right-hand gauge delivers reliable pass/fail results that help ensure proper fastener fit and reduce rework in production lines.

• Fast, go/no-go thread checks: Quickly identify whether 1/2 x 13 UNC threads conform or require adjustment, speeding up QA and setup decisions.
• Durable, grip-friendly construction: Knurled body and robust fittings provide secure handling and long service life in busy shop environments.
• UNC 2B compatibility for repeatable results: Precisely sized to the 1/2 x 13 UNC with 2B tolerances, delivering consistent measurements across parts and inspections.

The JBO Thread Plug Gauge helps streamline inspection workflows by delivering clear pass/fail results, reducing guesswork, and ensuring reliable thread engagement in assembled components. Its compact design makes it easy to bring to the job site or into the quality control area, supporting faster setup, fewer reworks, and confidence that parts meet Unified thread standards every time.