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Truthread Thread Ring Gauge (NoGo) - UNF - Right Hand - 2A - 1/2x20
| Thead Form | UNF |
| Size | 1/2 |
| Pitch | 20 |
| Gauge Type | Ring Gauge (NoGo) |
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The ones our customers buy most.Description
The Truthread Thread Ring Gauge (NoGo) is a precision measuring tool designed for Unified National Fine (UNF) threads. Sized for right-hand 1/2x20 threads in the 2A tolerance class, it helps machinists, inspectors, and technicians confirm that threaded parts stay within the approved size range.
Calibrated specifically for UNF threads, the NoGo gauge tests the minimum material condition to ensure the thread remains within the lower limit of the allowable size. This makes it ideal for identifying threaded parts that should not exceed the maximum allowable size, reducing rework and speeding up quality checks.
- UNF-thread calibration for accuracy: Precisely tuned for Unified National Fine threads, the gauge provides reliable go/no-go checks that reflect true threading tolerances, helping you trust every measurement.
- NoGo minimum material condition verification: The NoGo test confirms the thread remains within the lower limit of the spec, quickly flagging parts that would be out of tolerance and ensuring consistent fits.
- Right-hand 1/2x20, 2A size compatibility: Designed for common UNF right-hand threads at 1/2x20 and 2A class, it aligns with standard fasteners to minimize guesswork and the need for multiple gauges.
With this gauge in your toolkit, you gain faster, more reliable thread verification on the shop floor, higher first-pass acceptance rates, and less downtime due to rework. The clear go/no-go clarity supports consistent quality across parts and assemblies, giving engineers, buyers, and technicians confidence in every measurement and fit.
Part Numbers
- Protool Part Number
- PRO2100229
- Brand
- Truthread
- 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: Truthread Thread Ring Gauge's (NoGo) - UN - Right Hand - 2A
View full collection →You are viewing PRO2100229. Click any other SKU to view its full details.
| Product SKU | Thread Form | Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|---|
| PRO2100203 | UNC | No.4 | 40 | £80.14 | Out of Stock | |
| PRO2100204 | UNF | No.4 | 48 | £80.14 | In Stock | |
| PRO2100205 | UNC | No.5 | 40 | £80.14 | In Stock | |
| PRO2100206 | UNF | No.5 | 44 | £80.14 | In Stock | |
| PRO2100207 | UNC | No.6 | 32 | £62.96 | In Stock | |
| PRO2100208 | UNF | No.6 | 40 | £62.96 | In Stock | |
| PRO2100209 | UNC | No.8 | 32 | £62.96 | Out of Stock | |
| PRO2100210 | UNF | No.8 | 36 | £62.96 | In Stock | |
| PRO2100211 | UNC | No.10 | 24 | £62.96 | Out of Stock | |
| PRO2100212 | UNF | No.10 | 32 | £62.96 | Out of Stock | |
| PRO2100213 | UNC | No.12 | 24 | £62.96 | In Stock | |
| PRO2100214 | UNF | No.12 | 28 | £62.96 | In Stock | |
| PRO2100215 | UNEF | No.12 | 32 | £91.58 | In Stock | |
| PRO2100216 | UNC | 1/4 | 20 | £62.96 | In Stock | |
| PRO2100217 | UNF | 1/4 | 28 | £62.96 | In Stock | |
| PRO2100218 | UNEF | 1/4 | 32 | £91.58 | Out of Stock | |
| PRO2100219 | UNC | 5/16 | 18 | £62.96 | In Stock | |
| PRO2100220 | UNF | 5/16 | 24 | £62.96 | Out of Stock | |
| PRO2100221 | UNEF | 5/16 | 32 | £91.58 | In Stock | |
| PRO2100222 | UNC | 3/8 | 16 | £62.96 | In Stock | |
| PRO2100223 | UNF | 3/8 | 24 | £62.96 | In Stock | |
| PRO2100224 | UEF | 3/8 | 32 | £91.58 | In Stock | |
| PRO2100225 | UNC | 7/16 | 14 | £62.96 | Out of Stock | |
| PRO2100226 | UNF | 7/16 | 20 | £62.96 | Out of Stock | |
| PRO2100227 | UNEF | 7/16 | 28 | £91.58 | Out of Stock | |
| PRO2100228 | UNC | 1/2 | 13 | £62.96 | In Stock | |
| PRO2100229 Viewing | UNF | 1/2 | 20 | £62.96 | Out of Stock | |
| PRO2100230 | UNEF | 1/2 | 28 | £91.58 | Out of Stock | |
| PRO2100231 | UNC | 9/16 | 12 | £85.86 | In Stock | |
| PRO2100232 | UNF | 9/16 | 18 | £68.69 | Out of Stock | |
| PRO2100233 | UN | 9/16 | 20 | £114.48 | Out of Stock | |
| PRO2100234 | UNEF | 9/16 | 24 | £120.20 | In Stock | |
| PRO2100235 | UNC | 5/8 | 11 | £85.86 | In Stock | |
| PRO2100236 | UNF | 5/8 | 18 | £68.69 | Out of Stock | |
| PRO2100237 | UN | 5/8 | 20 | £114.48 | Out of Stock | |
| PRO2100238 | UNEF | 5/8 | 24 | £120.20 | In Stock | |
| PRO2100239 | UN | 11/16 | 12 | £114.48 | In Stock | |
| PRO2100240 | UN | 11/16 | 16 | £114.48 | In Stock | |
| PRO2100241 | UN | 11/16 | 20 | £120.20 | In Stock | |
| PRO2100242 | UNEF | 11/16 | 24 | £120.20 | In Stock | |
| PRO2100243 | UNC | 3/4 | 10 | £114.48 | In Stock | |
| PRO2100244 | UN | 3/4 | 12 | £114.48 | In Stock | |
| PRO2100245 | UNF | 3/4 | 16 | £85.86 | In Stock | |
| PRO2100246 | UNEF | 3/4 | 20 | £120.20 | Out of Stock | |
| PRO2100247 | UN | 13/16 | 12 | £137.38 | In Stock | |
| PRO2100248 | UN | 13/16 | 16 | £137.38 | In Stock | |
| PRO2100249 | UNEF | 13/16 | 20 | £137.38 | Out of Stock | |
| PRO2100250 | UNEF | 13/16 | 24 | £143.10 | Out of Stock | |
| PRO2100251 | UNC | 7/8 | 9 | £137.38 | Out of Stock | |
| PRO2100252 | UN | 7/8 | 12 | £128.79 | In Stock | |
| PRO2100253 | UNF | 7/8 | 14 | £85.86 | Out of Stock | |
| PRO2100254 | UN | 7/8 | 16 | £128.79 | In Stock | |
| PRO2100255 | UNEF | 7/8 | 20 | £128.79 | Out of Stock | |
| PRO2100256 | UN | 15/16 | 12 | £137.38 | In Stock | |
| PRO2100257 | UN | 15/16 | 16 | £137.38 | Out of Stock | |
| PRO2100258 | UNEF | 15/16 | 20 | £137.38 | In Stock | |
| PRO2100259 | UNC | 1 | 8 | £160.27 | In Stock | |
| PRO2100260 | UNF | 1 | 12 | £128.79 | In Stock | |
| PRO2100261 | UN | 1 | 14 | £128.79 | Out of Stock | |
| PRO2100262 | UN | 1 | 16 | £128.79 | In Stock | |
| PRO2100263 | UNEF | 1 | 20 | £128.79 | In Stock | |
| PRO2100264 | UNC | 1.1/16 | 8 | £214.65 | Out of Stock | |
| PRO2100265 | UNF | 1.1/16 | 12 | £137.38 | Out of Stock | |
| PRO2100266 | UN | 1.1/16 | 16 | £137.38 | In Stock | |
| PRO2100267 | UNEF | 1.1/16 | 18 | £214.65 | Out of Stock | |
| PRO2100268 | UNC | 1.1/8 | 7 | £214.65 | Out of Stock | |
| PRO2100269 | UNF | 1.1/8 | 12 | £128.79 | In Stock | |
| PRO2100270 | UN | 1.1/8 | 16 | £128.79 | Out of Stock | |
| PRO2100271 | UNEF | 1.1/8 | 18 | £214.65 | Out of Stock | |
| PRO2100272 | UN | 1.3/16 | 8 | £214.65 | Out of Stock | |
| PRO2100273 | UN | 1.3/16 | 12 | £137.38 | In Stock | |
| PRO2100274 | UN | 1.3/16 | 16 | £137.38 | In Stock | |
| PRO2100275 | UNEF | 1.3/16 | 18 | £214.65 | Out of Stock | |
| PRO2100276 | UNC | 1.1/4 | 7 | £214.65 | Out of Stock | |
| PRO2100277 | UN | 1.1/4 | 8 | £214.65 | Out of Stock | |
| PRO2100278 | UNF | 1.1/4 | 12 | £128.79 | Out of Stock | |
| PRO2100279 | UN | 1.1/4 | 16 | £128.79 | Out of Stock | |
| PRO2100280 | UNEF | 1.1/4 | 18 | £214.65 | Out of Stock | |
| PRO2100281 | UN | 1.1/4 | 20 | £214.65 | Out of Stock | |
| PRO2100282 | UN | 1.5/16 | 8 | £214.65 | Out of Stock | |
| PRO2100283 | UNF | 1.5/16 | 12 | £137.38 | Out of Stock | |
| PRO2100284 | UN | 1.5/16 | 16 | £137.38 | In Stock | |
| PRO2100285 | UNEF | 1.5/16 | 18 | £214.65 | Out of Stock | |
| PRO2100286 | UN | 1.5/16 | 20 | £214.65 | Out of Stock | |
| PRO2100287 | UNC | 1.3/8 | 6 | £228.96 | Out of Stock | |
| PRO2100288 | UN | 1.3/8 | 8 | £214.65 | In Stock | |
| PRO2100289 | UNF | 1.3/8 | 12 | £137.38 | Out of Stock | |
| PRO2100290 | UN | 1.3/8 | 16 | £137.38 | In Stock | |
| PRO2100291 | UNEF | 1.3/8 | 18 | £214.65 | Out of Stock | |
| PRO2100292 | UN | 1.3/8 | 20 | £214.65 | Out of Stock | |
| PRO2100293 | UN | 1.3/8 | 6 | £228.96 | Out of Stock | |
| PRO2100294 | UN | 1.3/8 | 8 | £214.65 | Out of Stock | |
| PRO2100295 | UN | 1.7/16 | 12 | £137.38 | In Stock | |
| PRO2100296 | UNEF | 1.7/16 | 18 | £214.65 | Out of Stock | |
| PRO2100297 | UN | 1.7/16 | 20 | £214.65 | Out of Stock | |
| PRO2100298 | UNC | 1.1/2 | 6 | £228.96 | Out of Stock | |
| PRO2100299 | UN | 1.1/2 | 8 | £214.65 | In Stock | |
| PRO2100300 | UNF | 1.1/2 | 12 | £137.38 | Out of Stock | |
| PRO2100301 | UN | 1.1/2 | 16 | £137.38 | In Stock | |
| PRO2100302 | UNEF | 1.1/2 | 18 | £214.65 | Out of Stock | |
| PRO2100303 | UN | 1.1/2 | 20 | £214.65 | Out of Stock |
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