The JBO Thread Plug Gauge is a precision UNC Go/No-Go inspection tool designed to verify threaded holes quickly and accurately. Specifically configured as Right Hand, 3B tolerance, and No. 4 x 40 size, it is ideal for manufacturing, automotive, and aerospace environments where fast, reliable thread checks are essential. This gauge helps you confirm hole conformity to Unified thread standards with clear go/no-go feedback, reducing guesswork in every inspection.

Built for dependable performance in daily QC use, the gauge features a rugged, knurled body and precisely machined ends to ensure repeatable seating and smooth operation across many cycles. Its compact design fits easily into tool cribs and inspection carts, enabling reliable measurements at the point of need.

• Go/No-Go design for fast pass/fail decisions: Enables quick, at-a-glance verification of thread hole quality, speeding up inspection and reducing handling time.
• Right Hand UNC compatibility (No. 4 x 40, 3B): Precisely matched to standard UNC threads, delivering accurate checks that align with common manufacturing specifications.
• Durable, knurled construction with precision ends: Delivers secure grip and consistent seating while withstanding daily shop-floor use for long service life.

This plug gauge helps you streamline your quality workflow, delivering consistent, reliable readings that support proper fitment and part performance. By enabling faster, more confident thread inspections, it reduces rework, minimizes downtime, and supports dependable, repeatable results across production runs.