The JBO Plug Gauge for UNC (STI) is a precision measuring tool designed specifically to inspect UNC thread inserts (STIs). It enables fast, reliable checks of pitch diameter and overall fit, making it ideal for manufacturers, automotive shops, aerospace maintenance teams, and quality control inspectors who need consistent, trustworthy results during assembly, auditing, and incoming inspection.

This gauge is configured for Right Hand use with a 2B tolerance and a 1/2 x 13 UNC size, calibrated under DAkkS standards to provide traceable, repeatable measurements that align with ANSI/ASME UNC STI specifications. Its purpose-built design supports accurate verification of threaded inserts while helping you maintain standardization across parts and processes.

• DAkkS-Calibrated, Traceable Accuracy: Ensures measurement results you can rely on, reducing rework and disputes by providing officially recognized, calibration-backed pitch diameter checks.
• UNC (STI) 1/2 x 13 Compatibility: Precisely tailored for standard UNC STI inserts, enabling quick, correct assessment of fit and function for common automotive, manufacturing, and aerospace applications.
• Right-Hand, 2B Precision: Built for dependable performance with a robust, easy-to-use design and tight tolerances, delivering consistent outcomes across multiple inspections and parts.

Used in quality assurance workflows, this plug gauge helps you verify inserts against spec, speeds up go/no-go checks, and strengthens confidence that each threaded insert will perform as intended in critical assemblies.