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Carmex Carbide Threading Insert - UNJ - TiAlN Coated - 21E20UNJ
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | External |
| Insert Size | 21 |
| Pitch | 20 |
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The Carmex Carbide Threading Insert for UNJ, TiAlN coated (model 21E20UNJ) is a versatile solution for precision threading across common profiles. Built for machinists and workshops that value consistent performance and long tool life.
- Material: Solid carbide substrate for rigidity and wear resistance in demanding threading operations.
- Coating: TiAlN coating enhances hardness and heat resistance, helping maintain cutting efficiency during high-temperature threading.
- Thread profiles: Covers all common thread profiles in one insert family, streamlining setup for diverse projects.
- Lengths: Five lengths available, from 12 mm to 40 mm, to fit different hole depths and workpiece geometries.
- Pitch range: Depending on length, capable of threading pitches from 0.5 mm (32 TPI) to 6.0 mm (4 TPI).
- Double cutting edges: Inserts are double-sided with two cutting edges (except for BSPT/NPT/NPTF/American Buttress/API RD variants) for extended use between indexings.
- Internal/External capability: For many thread profiles, the same insert can machine both internal and external threads, with exceptions for ISO/UN/NPSM/UNJ/Acme.
- Designation: 21E20UNJ, a precise identifier to ensure you select the UNJ-specific variant.
- Brand: Carmex, a trusted name in carbide tooling and threading solutions.
This insert is designed to deliver reliable thread quality with minimal tool changes thanks to its dual-edge design, while the TiAlN coating provides resilience under heat and friction. Its five length options let you tailor engagement and reach to your specific machining setup, helping you achieve consistent thread profiles across a variety of workpieces without inventory clutter. Ideal for shops performing both routine and mixed-threading tasks where durability and precision are essential.
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | External |
| Insert Size | 21 |
| Pitch | 20 |
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 21E20UNJ. 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 | 21 | 24 | £30.44 | 5 days | |
| 21I20UNJ | 21 | 20 | £30.44 | 5 days | |
| 21E20UNJ Viewing | 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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