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JBO Thread Ring Gauge (GO) - Metric Coarse - Left Hand - 6g - M18 x 2.5
| Thread Form | Metric |
| Size | M18 |
| Pitch | 2.5 |
| Gauge Type | Ring Gauge (GO) |
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The ones our customers buy most.Description
Designed for engineers, machinists, inspectors, and buyers, the JBO Thread Ring Gauge (GO) — Metric Coarse — Left Hand — 6g — M18 x 2.5 is a dedicated tool for quickly and reliably verifying external thread dimensions. Its precise GO dimension helps confirm whether a component's metric coarse threads meet specification, supporting fast, accurate quality checks in production or repair environments. Made from hardened steel for durability, it stands up to daily use and resists wear, ensuring long service life in busy workshops.
- Precise metric coarse GO gauge for M18 x 2.5 Left-Hand threads: Quickly verify external thread diameter and pitch to ensure components match specification, reducing inspection time and rework.
- Hardened steel construction for durability: Built to withstand daily use in busy workshops, resisting wear and maintaining accurate size checks over many cycles.
- 6g tolerance class for repeatable results: Delivers consistent measurements across multiple inspections, helping you trust every check and maintain process stability.
The JBO Thread Ring Gauge (GO) helps streamline quality control and precision assembly by providing fast, reliable checks of metric coarse external threads, including left-hand configurations like M18 x 2.5. Its rugged, wear-resistant body and tightly controlled dimensions support repeatable measurements, reducing downtime and ensuring components fit and function as intended in your applications.
Part Numbers
- Protool Part Number
- JBO-501666
- 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 Thread Ring Gauges (GO) - Metric Coarse
View full collection →You are viewing JBO-501666. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| JBO-501426 | M1 | 0.25 | £135.97 | 5 days | |
| JBO-501430 | M1.1 | 0.25 | £176.54 | 5 days | |
| JBO-501431 | M1.2 | 0.25 | £128.29 | 5 days | |
| JBO-501434 | M1.4 | 0.3 | £114.03 | 5 days | |
| JBO-501441 | M1.6 | 0.35 | £99.02 | 5 days | |
| JBO-501446 | M1.7 | 0.35 | £120.61 | 5 days | |
| JBO-501448 | M1.8 | 0.35 | £88.27 | 5 days | |
| JBO-501700 | M2 | 0.4 | £83.67 | 5 days | |
| JBO-501714 | M2.2 | 0.45 | £93.31 | 5 days | |
| JBO-501720 | M2.3 | 0.4 | £154.62 | 5 days | |
| JBO-501724 | M2.5 | 0.45 | £67.67 | 5 days | |
| JBO-501739 | M2.6 | 0.45 | £83.11 | 5 days | |
| JBO-501903 | M3 | 0.5 | £52.09 | 5 days | |
| JBO-501919 | M3.5 | 0.6 | £54.82 | 5 days | |
| JBO-502047 | M4 | 0.7 | £47.70 | 5 days | |
| JBO-502069 | M4.5 | 0.75 | £74.13 | 5 days | |
| JBO-502138 | M5 | 0.8 | £47.70 | 5 days | |
| JBO-502214 | M6 | 1 | £47.70 | 5 days | |
| JBO-502271 | M7 | 1 | £54.51 | 5 days | |
| JBO-502301 | M8 | 1.25 | £48.81 | 5 days | |
| JBO-502347 | M9 | 1.25 | £65.13 | 5 days | |
| JBO-501452 | M10 | 1.5 | £54.51 | 5 days | |
| JBO-501492 | M11 | 1.5 | £76.53 | 5 days | |
| JBO-501512 | M12 | 1.75 | £60.74 | 5 days | |
| JBO-501572 | M14 | 2 | £64.91 | 5 days | |
| JBO-501623 | M16 | 2 | £74.24 | 5 days | |
| JBO-501663 | M18 | 2.5 | £87.84 | 5 days | |
| JBO-501748 | M20 | 2.5 | £94.96 | 5 days | |
| JBO-501782 | M22 | 2.5 | £106.80 | 5 days | |
| JBO-501815 | M24 | 3 | £111.84 | 5 days | |
| JBO-501868 | M27 | 3 | £128.29 | 5 days | |
| JBO-501929 | M30 | 3.5 | £135.97 | 5 days | |
| JBO-501975 | M33 | 3.5 | £154.62 | 5 days | |
| JBO-502011 | M36 | 4 | £163.39 | 5 days | |
| JBO-502039 | M39 | 4 | £179.84 | 5 days | |
| JBO-502093 | M42 | 4.5 | £186.41 | 5 days | |
| JBO-502108 | M45 | 4.5 | £198.46 | 5 days | |
| JBO-502125 | M48 | 5 | £209.44 | 5 days | |
| JBO-502176 | M52 | 5 | £250.01 | 5 days | |
| JBO-502199 | M56 | 5.5 | £239.05 | 5 days | |
| JBO-502244 | M60 | 5.5 | £321.28 | 5 days | |
| JBO-502257 | M64 | 6 | £339.93 | 5 days | |
| JBO-502267 | M68 | 6 | £362.95 | 5 days | |
| JBO-501443 | M1.6 | 0.35 | £117.33 | 5 days | |
| JBO-501704 | M2 | 0.4 | £95.95 | 5 days | |
| JBO-501715 | M2.2 | 0.45 | £107.24 | 5 days | |
| JBO-501728 | M2.5 | 0.45 | £76.44 | 5 days | |
| JBO-501906 | M3 | 0.5 | £58.90 | 5 days | |
| JBO-501921 | M3.5 | 0.6 | £59.98 | 5 days | |
| JBO-502051 | M4 | 0.7 | £53.62 | 5 days | |
| JBO-502143 | M5 | 0.8 | £53.62 | 5 days | |
| JBO-502218 | M6 | 1 | £53.62 | 5 days | |
| JBO-502272 | M7 | 1 | £62.72 | 5 days | |
| JBO-502305 | M8 | 1.25 | £54.94 | 5 days | |
| JBO-502956 | M9 | 1.25 | £82.24 | 5 days | |
| JBO-501456 | M10 | 1.5 | £63.50 | 5 days | |
| JBO-501494 | M11 | 1.5 | £96.40 | 5 days | |
| JBO-501517 | M12 | 1.75 | £70.29 | 5 days | |
| JBO-501574 | M14 | 2 | £77.97 | 5 days | |
| JBO-501626 | M16 | 2 | £83.67 | 5 days | |
| JBO-501664 | M18 | 2.5 | £97.16 | 5 days | |
| JBO-501751 | M20 | 2.5 | £107.15 | 5 days | |
| JBO-501783 | M22 | 2.5 | £129.40 | 5 days | |
| JBO-501817 | M24 | 3 | £137.06 | 5 days | |
| JBO-501869 | M27 | 3 | £154.62 | 5 days | |
| JBO-501931 | M30 | 3.5 | £168.86 | 5 days | |
| JBO-504575 | M33 | 3.5 | £187.50 | 5 days | |
| JBO-503038 | M36 | 4 | £199.57 | 5 days | |
| JBO-518837 | M39 | 4 | £216.02 | 5 days | |
| JBO-501444 | M1.6 | 0.35 | £124.99 | 5 days | |
| JBO-501450 | M1.8 | 0.35 | £124.99 | 5 days | |
| JBO-501705 | M2 | 0.4 | £105.26 | 5 days | |
| JBO-506050 | M2.2 | 0.45 | £117.33 | 5 days | |
| JBO-501908 | M3 | 0.5 | £63.83 | 5 days | |
| JBO-501923 | M3.5 | 0.6 | £66.02 | 5 days | |
| JBO-502052 | M4 | 0.7 | £58.90 | 5 days | |
| JBO-502145 | M5 | 0.8 | £58.90 | 5 days | |
| JBO-502220 | M6 | 1 | £58.90 | 5 days | |
| JBO-502273 | M7 | 1 | £68.54 | 5 days | |
| JBO-502306 | M8 | 1.25 | £60.43 | 5 days | |
| JBO-502349 | M9 | 1.25 | £82.24 | 5 days | |
| JBO-501457 | M10 | 1.5 | £69.51 | 5 days | |
| JBO-501495 | M11 | 1.5 | £96.40 | 5 days | |
| JBO-501518 | M12 | 1.75 | £77.19 | 5 days | |
| JBO-501575 | M14 | 2 | £82.45 | 5 days | |
| JBO-501627 | M16 | 2 | £91.67 | 5 days | |
| JBO-501665 | M18 | 2.5 | £106.25 | 5 days | |
| JBO-501752 | M20 | 2.5 | £117.33 | 5 days | |
| JBO-501784 | M22 | 2.5 | £129.40 | 5 days | |
| JBO-501818 | M24 | 3 | £137.06 | 5 days | |
| JBO-501870 | M27 | 3 | £154.62 | 5 days | |
| JBO-501932 | M30 | 3.5 | £168.86 | 5 days | |
| JBO-503924 | M33 | 3.5 | £183.12 | 5 days | |
| JBO-502012 | M36 | 4 | £199.57 | 5 days | |
| JBO-503893 | M39 | 4 | £216.02 | 5 days | |
| JBO-503932 | M42 | 4.5 | £285.10 | 5 days | |
| JBO-506059 | M45 | 4.5 | £301.53 | 5 days | |
| JBO-505775 | M48 | 5 | £321.28 | 5 days | |
| JBO-506060 | M52 | 5 | £343.21 | 5 days | |
| JBO-501427 | M1 | 0.25 | £509.89 | 5 days | |
| JBO-506034 | M1.1 | 0.25 | £649.14 | 5 days | |
| JBO-501432 | M1.2 | 0.25 | £467.11 | 5 days | |
| JBO-501435 | M1.4 | 0.3 | £144.74 | 5 days | |
| JBO-501442 | M1.6 | 0.35 | £124.99 | 5 days | |
| JBO-501449 | M1.8 | 0.35 | £111.84 | 5 days | |
| JBO-501702 | M2 | 0.4 | £105.26 | 5 days | |
| JBO-503906 | M2.2 | 0.45 | £117.33 | 5 days | |
| JBO-501729 | M2.5 | 0.45 | £82.80 | 5 days | |
| JBO-501905 | M3 | 0.5 | £63.83 | 5 days | |
| JBO-501920 | M3.5 | 0.6 | £66.02 | 5 days | |
| JBO-502049 | M4 | 0.7 | £58.90 | 5 days | |
| JBO-502141 | M5 | 0.8 | £58.90 | 5 days | |
| JBO-502217 | M6 | 1 | £58.90 | 5 days | |
| JBO-502915 | M7 | 1 | £68.54 | 5 days | |
| JBO-502304 | M8 | 1.25 | £60.43 | 5 days | |
| JBO-502348 | M9 | 1.25 | £82.24 | 5 days | |
| JBO-501455 | M10 | 1.5 | £69.51 | 5 days | |
| JBO-501493 | M11 | 1.5 | £96.40 | 5 days | |
| JBO-501515 | M12 | 1.75 | £77.19 | 5 days | |
| JBO-503905 | M14 | 2 | £82.45 | 5 days | |
| JBO-501625 | M16 | 2 | £91.67 | 5 days | |
| JBO-503907 | M18 | 2.5 | £106.25 | 5 days | |
| JBO-501750 | M20 | 2.5 | £117.33 | 5 days | |
| JBO-503879 | M22 | 2.5 | £131.59 | 5 days | |
| JBO-503588 | M24 | 3 | £137.06 | 5 days | |
| JBO-503908 | M27 | 3 | £144.74 | 5 days | |
| JBO-501930 | M30 | 3.5 | £172.16 | 5 days | |
| JBO-506038 | M1.4 | 0.3 | £163.39 | 5 days | |
| JBO-505880 | M1.6 | 0.35 | £141.45 | 5 days | |
| JBO-501707 | M2 | 0.4 | £127.21 | 5 days | |
| JBO-501730 | M2.5 | 0.45 | £94.73 | 5 days | |
| JBO-501910 | M3 | 0.5 | £63.83 | 5 days | |
| JBO-501924 | M3.5 | 0.6 | £66.02 | 5 days | |
| JBO-502053 | M4 | 0.7 | £58.90 | 5 days | |
| JBO-502147 | M5 | 0.8 | £58.90 | 5 days | |
| JBO-502222 | M6 | 1 | £58.90 | 5 days | |
| JBO-502274 | M7 | 1 | £68.54 | 5 days | |
| JBO-502308 | M8 | 1.25 | £60.43 | 5 days | |
| JBO-502800 | M9 | 1.25 | £82.24 | 5 days | |
| JBO-501459 | M10 | 1.5 | £69.51 | 5 days | |
| JBO-503911 | M11 | 1.5 | £96.40 | 5 days | |
| JBO-501520 | M12 | 1.75 | £77.19 | 5 days | |
| JBO-501576 | M14 | 2 | £94.09 | 5 days | |
| JBO-501628 | M16 | 2 | £91.67 | 5 days | |
| JBO-501666 Viewing | M18 | 2.5 | £106.25 | 5 days | |
| JBO-501753 | M20 | 2.5 | £117.33 | 5 days | |
| JBO-501786 | M22 | 2.5 | £129.40 | 5 days | |
| JBO-501819 | M24 | 3 | £137.06 | 5 days | |
| JBO-501871 | M27 | 3 | £154.62 | 5 days | |
| JBO-501933 | M30 | 3.5 | £168.86 | 5 days | |
| JBO-501976 | M33 | 3.5 | £183.12 | 5 days | |
| JBO-502013 | M36 | 4 | £199.57 | 5 days | |
| JBO-502987 | M39 | 4 | £230.28 | 5 days | |
| JBO-503533 | M42 | 4.5 | £250.01 | 5 days | |
| JBO-503327 | M45 | 4.5 | £264.27 | 5 days | |
| JBO-503534 | M48 | 5 | £280.72 | 5 days | |
| JBO-503535 | M52 | 5 | £301.53 | 5 days | |
| JBO-503914 | M4 | 0.7 | £69.74 | 5 days | |
| JBO-502954 | M5 | 0.8 | £69.74 | 5 days | |
| JBO-502224 | M6 | 1 | £69.74 | 5 days | |
| JBO-502309 | M8 | 1.25 | £71.39 | 5 days | |
| JBO-503093 | M10 | 1.5 | £82.35 | 5 days | |
| JBO-503759 | M12 | 1.75 | £91.57 | 5 days | |
| JBO-503643 | M16 | 2 | £108.68 | 5 days | |
| JBO-503915 | M20 | 2.5 | £137.06 | 5 days |
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