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Carmex Carbide Threading Insert - UNJ - TiAlN Coated - 21E24UNJ
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | External |
| Insert Size | 21 |
| Pitch | 24 |
Learn more about Klarna
The Carmex Carbide Threading Insert - UNJ - TiAlN Coated (21E24UNJ) is a versatile, hard-wearing solution for precision threading on lathes and turning centers. Designed for professionals who need reliable performance across common thread profiles, it blends durability with flexible application in a single insert.
- TiAlN coating: Hard-wearing TiAlN coating boosts hardness and heat resistance for consistent cutting performance at higher speeds.
- UNJ threading compatibility: Specifically engineered to tackle UNJ thread forms, with broad coverage for many standard profiles.
- Five length options: Available in 5 lengths (from 12 mm to 40 mm) to fit a range of tools and workpiece depths.
- Pitch range: Depending on length, supports pitches from 0.5 mm (32 TPI) up to 6.0 mm (4 TPI) for versatile threading tasks.
- Double-edged inserts: Each insert provides two cutting edges for extended use (except for BSPT/NPT/NPTF/American Buttress/API RD where this may not apply).
- Internal & external capability: In many profiles, the same insert can machine both internal and external threads, reducing tool changes (with exceptions for ISO/UN/NPSM/UNJ/Acme).
- Carbide substrate: Solid carbide base delivers rigidity, wear resistance, and stable thread accuracy across multiple passes.
Designed for machinists who value efficiency and consistency, this insert helps you achieve accurate UNJ threads while maintaining tool life. The TiAlN coating minimizes built-up edge and heat, enabling reliable performance across a range of materials and turning speeds. Its versatile length options and broad pitch coverage mean fewer tool changes and a smaller inserts inventory, making it a practical choice for production runs and job shops alike.
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | External |
| Insert Size | 21 |
| Pitch | 24 |
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 Carbide Threading Inserts - UNJ - TiAlN Coated
View full collection →You are viewing 21E24UNJ. Click any other SKU to view its full details.
| Product SKU | Insert Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| 14I24UNJ | 14 | 24 | £22.91 | 5 days | |
| 14E24UNJ | 14 | 24 | £22.91 | 5 days | |
| 14I20UNJ | 14 | 20 | £22.91 | 5 days | |
| 14E20UNJ | 14 | 20 | £22.91 | 5 days | |
| 14I18UNJ | 14 | 18 | £29.81 | In Stock | |
| 14E18UNJ | 14 | 18 | £22.91 | 5 days | |
| 14I16UNJ | 14 | 16 | £22.91 | 5 days | |
| 14E16UNJ | 14 | 16 | £22.91 | 5 days | |
| 14I14UNJ | 14 | 14 | £22.91 | 5 days | |
| 14E14UNJ | 14 | 14 | £22.91 | 5 days | |
| 14I12UNJ | 14 | 12 | £22.91 | 5 days | |
| 14E12UNJ | 14 | 12 | £22.91 | 5 days | |
| 21I24UNJ | 21 | 24 | £30.44 | 5 days | |
| 21E24UNJ Viewing | 21 | 24 | £30.44 | 5 days | |
| 21I20UNJ | 21 | 20 | £30.44 | 5 days | |
| 21E20UNJ | 21 | 20 | £30.44 | 5 days | |
| 21I18UNJ | 21 | 18 | £30.44 | 5 days | |
| 21E18UNJ | 21 | 18 | £30.44 | 5 days | |
| 21I16UNJ | 21 | 16 | £30.44 | 5 days | |
| 21E16UNJ | 21 | 16 | £30.44 | 5 days | |
| 21I14UNJ | 21 | 14 | £30.44 | 5 days | |
| 21E14UNJ | 21 | 14 | £30.44 | 5 days | |
| 21I12UNJ | 21 | 12 | £39.62 | In Stock | |
| 21E12UNJ | 21 | 12 | £30.44 | 5 days |
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