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JBO Thread Ring Gauge (GO) - BSF - Right Hand - Medium Class - 3/8 x 20

SKU:JBO-502500

Meet the JBO Thread Ring Gauge (GO) for BSF—your go-to tool for verifying external thread diameters on right-hand BSF fasteners. Designed for machinists, inspectors, and production teams, it prov... Read more ↓
Thread FormBSF
Size3/8
Pitch20
Gauge TypeRing Gauge (GO)
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£105.26
Prices shown ex. VAT
5 days estimated lead time — subject to availability
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Free delivery over £50 ex VAT
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14-day returns
30+ years expertise
Klarna
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01732 887334
Mon – Thurs 8:30 – 17:30 · Fri 8:30 – 16:30

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Description

Meet the JBO Thread Ring Gauge (GO) for BSF—your go-to tool for verifying external thread diameters on right-hand BSF fasteners. Designed for machinists, inspectors, and production teams, it provides fast, reliable GO checks to confirm the 3/8 x 20 BSF size with medium-class tolerance is met. Built for daily use in busy workshops, this gauge combines precise dimensions with robust materials to deliver consistent results over time.

  • Go/No-Go quick checks: Enables fast GO testing of external threads to verify diameter and pitch accuracy, speeding inspections and reducing rework in quality control.
  • Durable hardened steel construction: Withstands wear and heavy use, maintaining measurement accuracy and extending service life in demanding shop environments.
  • BSF Right-Hand 3/8 x 20, Medium Class accuracy: Precisely matched to the specified BSF right‑hand thread and tolerance, delivering reliable, repeatable results across parts and suppliers.

This gauge streamlines inspection workflows by providing a clear, tactile check for properly conforming threads. Its dedicated sizing and rugged build support consistent results, helping you meet tight production schedules, reduce downtime, and maintain high-quality standards across projects.

Part Numbers

Protool Part Number
JBO-502500
Brand
JBO
Category
Gauge
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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: JBO Thread Ring Gauges (GO) - BSF

View full collection →

You are viewing JBO-502500. Click any other SKU to view its full details.

Product SKUSizePitchPriceStock Order
JBO-540040 3/1632£100.34 5 days
JBO-520234 7/3228£108.02 5 days
JBO-502498 1/426£92.89 5 days
JBO-520235 9/3226£108.02 5 days
JBO-502501 5/1622£97.49 5 days
JBO-502500 Viewing3/820£105.26 5 days
JBO-520236 7/1618£114.03 5 days
JBO-502497 1/216£116.23 5 days
JBO-507251 9/1616£129.40 5 days
JBO-520237 5/814£132.68 5 days
JBO-520238 11/1614£161.19 5 days
JBO-502499 3/412£150.21 5 days
JBO-540035 7/811£168.86 5 days
JBO-502496 110£194.08 5 days

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