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Carmex Carbide Threading Insert - UNJ - TiAlN Coated - 21I24UNJ
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | Internal |
| Insert Size | 21 |
| Pitch | 24 |
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The Carmex Carbide Threading Insert - UNJ, TiAlN coated, model 21I24UNJ is a versatile threading solution designed for professionals who machine UNJ and related thread forms. Built for durability and precise results, it covers a broad range of common thread profiles with a single, efficient insert.
- Five-length range: Available in five lengths from 12 mm to 40 mm to suit different hole depths and shoulders without changing inserts.
- Wide pitch compatibility: Supports pitches from 0.5 mm (32 TPI) up to 6.0 mm (4 TPI) to match a wide variety of standards.
- Double-sided cutting edges: Each insert typically has two cutting edges for extended life, improving productivity (exceptions apply for BSPT, NPT, NPTF, American Buttress, and API RD profiles).
- Internal & external threading capability: For many thread profiles, the same insert can machine both internal and external threads, offering flexibility and reducing tool inventory (note: ISO/UN/NPSM/UNJ/Acme profiles may require specific considerations).
- TiAlN-coated carbide construction: The TiAlN coating enhances wear resistance and heat tolerance, promoting longer tool life in demanding threading operations.
Designed for reliability in professional workshops, this UNJ-threading insert delivers consistent thread quality across common profiles. Its versatile length options, broad pitch coverage, and coating work together to reduce tool changes, speed up production, and simplify your threading workflow. Ideal for shops handling UNJ and related thread forms, it supports both routine and more challenging threading tasks with confidence.
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | Internal |
| 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 21I24UNJ. 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 Viewing | 21 | 24 | £30.44 | 5 days | |
| 21E24UNJ | 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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