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Carmex Thread Mills Solid Carbide - With Through Coolant - UNJ (UNJC UNJF UNJEF UNJS) - 5/16 x 24 - MT7
| Thread Form | UNJ (UNJC UNJF UNJEF UNJS) |
| Size | 5/16 |
| Pitch | 24 |
| Diameter (D) | 6.6 |
| Flute Length (l) | 16.4 |
| Shank Diameter (d) | 8 |
Learn more about Klarna
Introducing Carmex MTB Through-Coolant Thread Mills—the solid carbide tool designed for high-precision UNJ internal threading. Built for shops that demand consistent chip evacuation and longer tool life, this through-coolant solution keeps your machining process smooth from start to finish.

- Through-Coolant Bore: coolant flows through the tool bore to assist chip evacuation and maintain cutting efficiency, reducing heat and improving surface finish.
- Solid Carbide Construction: rigid, wear-resistant composition for stable threading and repeatable results in demanding applications.
- UNJ Thread Milling Capability: supports UNJC, UNJF, UNJEF, and UNJS thread forms for versatile internal threading needs.
- Size and Interface: 5/16 x 24 thread size with an MT7 shank for compatibility with common machining centers and holders.
- MTB Line Innovation: part of Carmex’s MTB progression, delivering enhanced cooling, durability, and consistent performance in precision threading tasks.
- Precision Internal Thread Milling: engineered for clean, accurate threads in through-coolant setups, reducing recuts and improving part quality.
The through-coolant design isn’t just about cooling—it actively supports chip control, extends tool life, and enables more stable, productive threading cycles. With UNJ compatibility and a robust solid carbide body, this Carmex MTB thread mill is a reliable choice for precision engineers tackling internal threads in a range of components. The MT7 shank ensures straightforward integration into existing setups, helping you achieve precise thread profiles with fewer runouts and consistent results from part to part.
| Thread Form | UNJ (UNJC UNJF UNJEF UNJS) |
| Size | 5/16 |
| Pitch | 24 |
| Diameter (D) | 6.6 |
| Flute Length (l) | 16.4 |
| Shank Diameter (d) | 8 |
| No of Flutes | 4 |
| Overall Length (L) | 64 |
| Thread Mill Style | Standard + Coolant |
| Internal or External | Internal |
| Coating | MT7 |
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: Carmex Solid Carbide Thread Mills - UNJ - With Through Coolant (MTB)
View full collection →You are viewing MTB08066D1624UNJMT7. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Flute Length | Reach | Shank Diameter | Overall Length | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|---|
| MTB06048C1320UNJMT7 | 1/4 | 20 | 13.3 | 13.3 | 6 | 58 | £80.21 | 5 days | |
| MTB06052D1328UNJMT7 | 1/4 | 28 | 13.2 | 13.2 | 6 | 58 | £80.21 | 5 days | |
| MTB0606C1618UNJMT7 | 5/16 | 18 | 16.2 | 16.2 | 6 | 58 | £80.21 | 5 days | |
| MTB08066D1624UNJMT7 Viewing | 5/16 | 24 | 16.4 | 16.4 | 8 | 64 | £106.82 | 5 days | |
| MTB08074D1916UNJMT7 | 3/8 | 16 | 19.9 | 19.9 | 8 | 64 | £106.82 | 5 days | |
| MTB10082D1924UNJMT7 | 3/8 | 24 | 19.6 | 19.6 | 10 | 73 | £123.23 | 5 days | |
| MTB10085D2214UNJMT7 | 7/16 | 14 | 22.7 | 22.7 | 10 | 73 | £123.23 | 5 days | |
| MTB10092D2220UNJMT7 | 7/16 - 1/2 | 20 | 22.2 | 22.2 | 10 | 73 | £123.23 | 5 days | |
| MTB10098D2613UNJMT7 | 1/2 | 13 | 26.4 | 26.4 | 10 | 73 | £123.23 | 5 days | |
| MTB12116D2812UNJMT7 | 9/16 | 12 | 28.6 | 28.6 | 12 | 84 | £154.20 | 5 days |
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