Please log in here to access all benefits, including promotional discounts and faster checkouts.

VCOIL Plug Gauge (GO) - UNF (STI) - Heli Coil Gauge - Right Hand - 3B - 1.3/8 x 12

SKU:TC-19940

Precise GO plug gauge for UNF (STI) right-hand threads, purpose-built for Helicoil insert applications. Ideal for workshop and quality-control environments that strictly follow ANSI/ASME thread st... Read more ↓
Thread FormUNF (STI)
Size1.3/8
Pitch12
Gauge TypePlug Gauge (GO)
View all specifications ↓
£201.40
Prices shown ex. VAT
7 days estimated lead time — subject to availability
View Other Sizes →
Free delivery over £50 ex VAT
Secure checkout
14-day returns
30+ years expertise
Klarna
Pay in 3 interest-free instalments. No extra cost if paid on time. 18+ only.
Learn more about Klarna
Speak to our team
01732 887334
Mon – Thurs 8:30 – 17:30 · Fri 8:30 – 16:30

Compatible certification

The ones our customers buy most.

Description

Precise GO plug gauge for UNF (STI) right-hand threads, purpose-built for Helicoil insert applications. Ideal for workshop and quality-control environments that strictly follow ANSI/ASME thread standards.

  • Gauge Type: GO thread plug gauge used to verify that the thread cut in a part will screw in by hand without excessive force.
  • Thread System: UNF (STI) – Right Hand
  • Thread Size: 1.3/8 x 12 UNF
  • Size Class: 3B
  • Calibration & Standards: Manufactured to ANSI/ASME thread standards; factory calibration certificate available on request; calibrated at an independent measurement laboratory to DIN, ISO, and ANSI specifications using IAC thread scanners; reference temperature 20°C.

Benefits: Use this gauge to quickly confirm that threaded holes meet the required UNF specifications for Helicoil installations, helping to prevent misfits and scrap. The combination of hand-screw test, traceable calibration options, and ISO/DIN/ANSI alignment provides reliable pass/fail decisions and supports rigorous quality control in production and maintenance environments.

Part Numbers

Protool Part Number
TC-19940
Brand
VCOIL
Category
Gauge
No downloads are attached to this product yet.
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.

Ask our technical team about this tool

Not sure if this is the right tool for your job? Ask us about speeds and feeds, material suitability, holders or alternatives — 30+ years of machining experience on the other end.

Prefer to talk? Call 01732 887334 — Mon–Thurs 8:30–17:30, Fri 8:30–16:30.

Full Range: VCOIL Plug Gauges UNF (STI)

View full collection →

You are viewing TC-19940. Click any other SKU to view its full details.

Product SKUSizePitchPriceStock Order
TC-19823 No. 448£102.03 In Stock
TC-19824 No. 640£102.03 In Stock
TC-19825 No. 836£98.05 In Stock
TC-19826 No. 1032£98.05 7 days
TC-19827 1/428£95.40 7 days
TC-19828 5/1624£99.38 7 days
TC-19829 3/824£103.35 7 days
TC-19830 7/1620£108.65 In Stock
TC-19831 1/220£113.95 7 days
TC-19832 9/1618£123.23 In Stock
TC-19833 5/818£137.80 In Stock
TC-19834 3/416£169.60 7 days
TC-19835 7/814£184.18 7 days
TC-19836 112£221.28 7 days
TC-19837 114£221.28 7 days
TC-19838 1.1/812£221.28 7 days
TC-19839 1.1/412£257.05 7 days
TC-19840 1.3/812£166.95 7 days
TC-19841 1.3/812£166.95 7 days
TC-19842 1.1/212£194.78 7 days
TC-19843 1.1/212£194.78 7 days
TC-19923 No. 448£121.90 7 days
TC-19924 No. 640£121.90 7 days
TC-19925 No. 836£116.60 7 days
TC-19926 No. 1032£116.60 7 days
TC-19927 1/428£115.28 7 days
TC-19928 5/1624£119.25 7 days
TC-19929 3/824£123.23 7 days
TC-19930 7/1620£129.85 7 days
TC-19931 1/220£136.48 7 days
TC-19932 9/1618£148.40 7 days
TC-19933 5/818£165.63 7 days
TC-19934 3/416£202.73 7 days
TC-19935 7/814£221.28 7 days
TC-19936 112£265.00 7 days
TC-19937 114£265.00 7 days
TC-19938 1.1/812£265.00 7 days
TC-19939 1.1/412£308.73 7 days
TC-19940 Viewing1.3/812£201.40 7 days
TC-19941 1.3/812£201.40 7 days
TC-19942 1.1/212£234.53 7 days
TC-19943 1.1/212£234.53 7 days

Other sizes in this range

with tools we think you'll like
All 42 →