Please log in here to access all benefits, including promotional discounts and faster checkouts.

Carmex Carbide Threading Insert - Unified - TiAlN Coated - 21E24UN
| Application | Threading |
| Thread Form | UN |
| Internal or External | External |
| Insert Size | 21 |
| Pitch | 24 |
Learn more about Klarna
The Carmex Carbide Threading Insert is a unified-thread, TiAlN-coated solution built for machinists and production shops that demand precise, dependable threading across common profiles.
- Coating: TiAlN-coated carbide inserts for enhanced hardness and heat resistance, helping maintain cutting performance in demanding materials.
- Thread profiles coverage: A versatile collection that covers all common thread forms, designed to minimize tool changes and maximize setup flexibility.
- Lengths: Five available lengths ranging from 12 mm to 40 mm to suit different workpiece sizes and access needs.
- Pitch range: Capable of threading pitches from 0.5 mm (32 TPI) to 6.0 mm (4 TPI), enabling a wide array of standard screws and fasteners.
- Double-sided edges: Each insert provides two cutting edges (double-sided) to extend tool life, with exceptions for BSPT/NPT/NPTF/American Buttress/API RD profiles.
- Internal/External threading capability: For many thread profiles, the same insert can machine both internal and external threads, reducing tooling complexity—note: ISO/UN/NPSM/UNJ/Acme profiles have specific exclusions.
- Designation: Unified 21E24UN threading insert for standardized performance across common applications.
Designed for reliability in job shops and production environments, this insert reduces tool changes and inventory complexity while delivering consistent thread quality. The TiAlN coating helps sustain performance in higher-temperature cuts, and the double-edged design means fewer insert replacements during a run. Whether you’re tackling internal bores or external threads, this unified solution covers a broad range of profiles with solid, repeatable results.
| Application | Threading |
| Thread Form | UN |
| 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 - Unified - TiAlN Coated
View full collection →You are viewing 21E24UN. Click any other SKU to view its full details.
| Product SKU | Insert Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| 12I16UN | 12 | 16 | £26.50 | In Stock | |
| 12I18UN | 12 | 18 | £26.50 | 5 days | |
| 12I20UN | 12 | 20 | £26.50 | In Stock | |
| 12I24UN | 12 | 24 | £26.50 | 5 days | |
| 12I28UN | 12 | 28 | £26.50 | In Stock | |
| 12I32UN | 12 | 32 | £26.50 | In Stock | |
| 14E10UN | 14 | 10 | £32.37 | 5 days | |
| 14E11UN | 14 | 11 | £32.37 | 5 days | |
| 14E12UN | 14 | 12 | £26.50 | In Stock | |
| 14E14UN | 14 | 14 | £26.50 | In Stock | |
| 14E16UN | 14 | 16 | £26.50 | In Stock | |
| 14E18UN | 14 | 18 | £26.50 | 5 days | |
| 14E20UN | 14 | 20 | £26.50 | In Stock | |
| 14E24UN | 14 | 24 | £26.50 | In Stock | |
| 14E28UN | 14 | 28 | £26.50 | In Stock | |
| 14E32UN | 14 | 32 | £26.50 | 5 days | |
| 14I10UN | 14 | 10 | £26.50 | In Stock | |
| 14I11UN | 14 | 11 | £26.50 | In Stock | |
| 14I12UN | 14 | 12 | £26.50 | In Stock | |
| 14I14UN | 14 | 14 | £26.50 | 5 days | |
| 14I16UN | 14 | 16 | £26.50 | In Stock | |
| 14I18UN | 14 | 18 | £26.50 | In Stock | |
| 14I20UN | 14 | 20 | £26.50 | In Stock | |
| 14I24UN | 14 | 24 | £26.50 | In Stock | |
| 14I27UN | 14 | 27 | £26.50 | In Stock | |
| 14I28UN | 14 | 28 | £26.50 | In Stock | |
| 14I32UN | 14 | 32 | £26.50 | In Stock | |
| 14I9UN | 14 | 9 | £26.50 | In Stock | |
| 21E10UN | 21 | 10 | £35.22 | 5 days | |
| 21E11UN | 21 | 11 | £43.03 | 5 days | |
| 21E12UN | 21 | 12 | £35.22 | 5 days | |
| 21E14UN | 21 | 14 | £35.22 | 5 days | |
| 21E16UN | 21 | 16 | £35.22 | In Stock | |
| 21E18UN | 21 | 18 | £35.22 | In Stock | |
| 21E20UN | 21 | 20 | £35.22 | In Stock | |
| 21E24UN Viewing | 21 | 24 | £35.22 | In Stock | |
| 21I10UN | 21 | 10 | £35.22 | In Stock | |
| 21I12UN | 21 | 12 | £35.22 | 5 days | |
| 21I14UN | 21 | 14 | £35.22 | In Stock | |
| 21I16UN | 21 | 16 | £35.22 | In Stock | |
| 21I18UN | 21 | 18 | £35.22 | In Stock | |
| 21I20UN | 21 | 20 | £35.22 | In Stock | |
| 21I24UN | 21 | 24 | £35.22 | In Stock | |
| 21I7UN | 21 | 7 | £35.22 | In Stock | |
| 21I8UN | 21 | 8 | £35.22 | In Stock | |
| 30E10UN | 30 | 10 | £48.30 | 5 days | |
| 30E12UN | 30 | 12 | £48.30 | 5 days | |
| 30E14UN | 30 | 14 | £48.30 | 5 days | |
| 30E16UN | 30 | 16 | £48.30 | 5 days | |
| 30E18UN | 30 | 18 | £48.30 | 5 days | |
| 30E20UN | 30 | 20 | £48.30 | 5 days | |
| 30E6UN | 30 | 6 | £48.30 | 5 days | |
| 30E8UN | 30 | 8 | £48.30 | 5 days | |
| 30I10UN | 30 | 10 | £48.30 | 5 days | |
| 30I12UN | 30 | 12 | £48.30 | In Stock | |
| 30I14UN | 30 | 14 | £48.30 | 5 days | |
| 30I16UN | 30 | 16 | £48.30 | 5 days | |
| 30I18UN | 30 | 18 | £48.30 | In Stock | |
| 30I20UN | 30 | 20 | £48.30 | 5 days | |
| 30I5UN | 30 | 5 | £48.30 | In Stock | |
| 30I6UN | 30 | 6 | £48.30 | 5 days | |
| 30I8UN | 30 | 8 | £48.30 | 5 days | |
| 40E10UN | 40 | 10 | £83.54 | 5 days | |
| 40E12UN | 40 | 12 | £83.54 | 5 days | |
| 40E14UN | 40 | 14 | £83.54 | 5 days | |
| 40E16UN | 40 | 16 | £83.54 | 5 days | |
| 40E6UN | 40 | 6 | £83.54 | 5 days | |
| 40E8UN | 40 | 8 | £83.54 | 5 days | |
| 40I10UN | 40 | 10 | £83.54 | 5 days | |
| 40I12UN | 40 | 12 | £83.54 | 5 days | |
| 40I14UN | 40 | 14 | £83.54 | 5 days | |
| 40I16UN | 40 | 16 | £83.54 | 5 days | |
| 40I4.5UN | 40 | 4.5 | £83.54 | 5 days | |
| 40I4UN | 40 | 4 | £83.54 | 5 days | |
| 40I6UN | 40 | 6 | £83.54 | 5 days | |
| 40I8UN | 40 | 8 | £83.54 | 5 days |
No products match your filters.


