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JBO Plug Gauge - UNC (STI) Heli Coil Gauge - Right Hand - 2B - No. 4 x 40 - Calibrated (DAkkS Calibration)
| Thread Form | UNC (STI) |
| Size | No. 4 |
| Pitch | 40 |
| Gauge Type | Plug Gauge (D/E) |
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Description
The JBO Plug Gauge for UNC (STI) is a precision inspection tool built to verify UNC screw-thread inserts (STIs). Part of the Helicoil gauge family, it’s ideal for engineers, buyers, technicians, and inspectors who need fast, reliable checks on No. 4 x 40 inserts to ensure proper seating and performance in assemblies.
Manufactured and assessed to ANSI/ASME UNC standards, this plug gauge provides accurate pitch-diameter checks for UNC STI inserts. It features a right-hand orientation and DAkkS-calibrated accuracy, delivering traceable measurements you can trust for quality control across automotive, aerospace, and general manufacturing environments.
- DAkkS-calibrated, traceable accuracy: The gauge is calibrated to DAkkS standards, ensuring measurements you can rely on for audits, certifications, and consistent production quality.
- Designed for UNC (STI) wire inserts: Specifically built to verify pitch diameter and UNC STI specifications, helping you confirm proper fit of No. 4 x 40 inserts.
- Right-hand orientation with a durable, knurled body: The ergonomic, easy-to-grip design supports repeatable readings in busy work zones and enhances reliability over long-term use.
Using the JBO UNC plug gauge streamlines quality checks, ensures consistent insert fit, and delivers dependable readings across shifts. With DAkkS calibration, ANSI/ASME accuracy, and a rugged construction, this gauge supports confident, efficient inspections for manufacturing, automotive, and aerospace applications.
Part Numbers
- Protool Part Number
- JBO-512692
- Brand
- JBO
- Category
- Gauge
Need cutting data? Call 01732 887334 or email sales@protool-ltd.co.uk.
Delivery
Free UK mainland delivery on orders over £50 ex VAT. In-stock items ordered before 4:30pm are dispatched the same working day. Full delivery information.
Returns
14-day returns on unused stock items in original packaging. Special-order and bespoke tooling is non-returnable. Read our returns policy.
Technical Support
Over 30 years of machining experience behind the counter. Call 01732 887334, Mon–Thurs 8:30–17:30, Fri 8:30–16:30.
Trade Accounts
Credit accounts, contract pricing and scheduled call-off orders available for trade customers. Apply for an account.
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.
Full Range: JBO Plug Gauge UNC Heli Coil - Right Hand - 3B - Calibrated (DAkkS Calibration)
View full collection →You are viewing JBO-512692. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| JBO-512689 | No. 2 | 56 | £167.77 | 5 days | |
| JBO-512692 Viewing | No. 4 | 40 | £214.08 | 5 days | |
| JBO-512694 | No. 5 | 40 | £212.97 | 5 days | |
| JBO-512695 | No. 6 | 32 | £197.63 | 5 days | |
| JBO-512697 | No. 8 | 32 | £189.95 | 5 days | |
| JBO-512687 | No. 10 | 24 | £187.75 | 5 days | |
| JBO-512688 | No. 12 | 24 | £204.20 | 5 days | |
| JBO-512700 | 1/4 | 20 | £187.75 | 5 days | |
| JBO-512703 | 5/16 | 18 | £197.63 | 5 days | |
| JBO-512702 | 3/8 | 16 | £211.89 | 5 days | |
| JBO-512699 | 1/2 | 13 | £306.19 | 5 days | |
| JBO-512704 | 5/8 | 11 | £319.34 | 5 days | |
| JBO-513095 | No. 4 | 48 | £227.23 | 5 days | |
| JBO-512707 | No. 6 | 40 | £206.40 | 5 days | |
| JBO-512709 | No. 8 | 36 | £195.44 | 5 days | |
| JBO-512705 | No. 10 | 32 | £187.75 | 5 days | |
| JBO-512712 | 1/4 | 28 | £187.75 | 5 days | |
| JBO-512716 | 5/16 | 24 | £197.63 | 5 days | |
| JBO-512715 | 3/8 | 24 | £211.89 | 5 days | |
| JBO-513343 | 7/16 | 20 | £246.96 | 5 days | |
| JBO-512711 | 1/2 | 20 | £306.19 | 5 days | |
| JBO-512718 | 5/8 | 18 | £316.05 | 5 days | |
| JBO-512693 | No. 4 | 40 | £298.51 | 5 days | |
| JBO-512696 | No. 6 | 32 | £274.37 | 5 days | |
| JBO-512698 | No. 8 | 32 | £263.41 | 5 days | |
| JBO-512706 | No. 10 | 32 | £259.03 | 5 days | |
| JBO-512713 | 1/4 | 28 | £259.03 | 5 days | |
| JBO-512717 | UNF (STI) | 5/16 | £275.48 | 5 days |
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