The JBO Plug Gauge - UNF (STI) Helicoil Gauge is a precision, calibrated tool for inspecting UNF/STI threaded inserts. Built as a right-hand gauge with 2B tolerance and No. 4 x 48 length, it delivers consistent go/no-go verification in demanding manufacturing environments. Calibrated with DAkkS traceability, it provides reliable measurements for quality control and audits.

Manufactured and assessed in accordance with ANSI standards by the American National Standards Institute / ASME thread system, the JBO Plug Gauges - UNC (STI) Wire Inserts are precision measuring tools designed for UNC (Unified National Coarse) Screw Thread Inserts (STIs). These plug gauges enable efficient inspection of threaded inserts, verifying their compliance with UNC STI standards and specifications, and they allow for the measurement of pitch diameter to ensure proper fit and functionality.

• DAkkS-calibrated accuracy: DAkkS calibration provides traceable, ISO-compliant measurement results for quality control and audits, giving confidence in every check.
• ANSI/ASME UNC STI standard-aligned design: Manufactured to ANSI/ASME thread standards for UNC STI inserts, ensuring consistent fit and reliable inspection results across manufacturing, automotive, and aerospace applications.
• Precise pitch-diameter verification: Enables quick go/no-go checks for threaded inserts, helping reduce rework and speed up inspections while maintaining tight tolerances.

Using this gauge streamlines your inspection workflow by providing a single, calibrated reference for UNC/STI insert measurements, enabling faster verification and higher first-pass acceptance. The durable construction and precise dimensions support long service life in busy shop floors, while DAkkS calibration ensures your data stands up to audits and customer requirements. Whether you’re building engines, assembling equipment, or quality-checking components, this plug gauge helps you deliver consistent, dependable results every time.