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JBO Plug Gauge - UNF (STI) Heli Coil Gauge - Right Hand - 2B - No. 4 x 48 - Calibrated (DAkkS Calibration)

SKU:JBO-513095

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 deli... Read more ↓
Thread FormUNF (STI)
SizeNo. 4
Pitch48
Gauge TypePlug Gauge (D/E)
Thread DirectionRight Hand
Tolerance2B
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£164.47
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5 days estimated lead time — subject to availability
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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.

Thread Form UNF (STI)
Size No. 4
Pitch 48
Gauge Type Plug Gauge (D/E)
Thread Direction Right Hand
Tolerance 2B
Calibration DAkkS Calibration Cert

What time are Protool open?

We are open Monday to Friday between 8:30am and 5pm.

Do you offer Free Next Day delivery?

Yes! We offer Free Next Day delivery via Royal Mail Tracked 24 on all orders over £50 ex VAT*. We also offer Free DPD Local Next Day delivery on all orders over £100 ex VAT*.

We also offer the following:

  • Royal Mail Tracked 24 — £5.90 (FREE on orders over £50 ex VAT*). Order before 4:30pm for next day delivery. No signature required.
  • DPD Local Next Day — £8.00 (FREE on orders over £100 ex VAT*). Standard next day delivery to UK mainland addresses.
  • Royal Mail Special Delivery — £12.50. Guaranteed delivery before 1pm the next working day.
  • DPD Saturday Delivery — £25.00. Must be ordered on Friday before 4pm. Pre-12pm delivery.

For delivery to Scottish Highlands & Islands, Northern Ireland, Republic of Ireland, or overseas locations, additional charges apply. Please see our delivery page for full details, or call us on 01732 887 334.

*T's & C's and exclusions apply. Please see our delivery page for more information on all our services.

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Full Range: JBO Plug Gauge UNC Heli Coil - Right Hand - 3B - Calibrated (DAkkS Calibration)

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You are viewing JBO-513095. Click any other SKU to view its full details.

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JBO-512717 UNF (STI)5/16£212.72 5 days

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