The JBO Thread Plug Gauge is a precision inspection tool designed for professionals across manufacturing, automotive, and aerospace environments. It enables fast, reliable verification of threaded holes, helping teams confirm they meet Unified thread standards without guesswork.

This UNJF Go-No/Go gauge is sized for right-hand threads of 9/16 x 18 with a 3B tolerance. Its go/no-go design delivers quick pass/fail clarity, so inspectors and machinists can validate fitment on first contact and keep production moving smoothly.

• Go/No-Go Quick Check: Quickly determine if the hole conforms to the UNJF 9/16 x 18 right-hand, 3B specification, enabling fast pass/fail decisions and reducing setup time.
• Precision and Repeatability: Manufactured to tight UNJF dimensions to deliver consistent, repeatable checks across parts and lots, helping you maintain tight process control.
• User-Friendly, Durable Construction: Knurled grip and robust ends give you secure handling and reliable alignment in busy workshops, improving accuracy and reducing tool fatigue.

In everyday use, the JBO Thread Plug Gauge helps streamline quality control, shorten inspection time, and ensure threaded holes meet spec consistently. Its robust design supports reliable performance across high-volume workloads, so you can trust it to deliver accurate results from the first part to the last.