The JBO Thread Plug Gauge is a precision go/no-go tool designed to verify UNJF (Unified National Fine) thread holes with consistent, fast results. It's ideal for inspectors, machinists, and quality teams across manufacturing, automotive, and aerospace environments where accurate thread checks matter. Use it to confirm that a hole meets exact UNJF specifications and to quickly identify nonconforming threads before assembly.

Sized No. 6 x 40 with right-hand orientation and 3B tolerance, this gauge delivers reliable, repeatable checks that you can depend on in daily QC workflows. Its compact, robust construction fits easily into toolkits and inspection benches, helping you move from measurement to action with confidence.

• Go/No-Go design: Quickly distinguish compliant from nonconforming threads, accelerating inspections and reducing guesswork or rework.
• UNJF 3B compatibility: Precisely calibrated to UNJF 3B standards, ensuring accurate verification of threaded holes in line with established specifications.
• Ergonomic, durable construction: Knurled, rugged body and reliable end fittings provide a secure grip and long tool life in busy shop environments.

This plug gauge supports cleaner workflows by delivering clear pass/fail results, helping you maintain consistent threading quality, reduce downtime, and ensure reliable fitment across production runs and assemblies.