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Carmex Carbide Threading Insert - Unified - TiAlN Coated - 21E20UN
| Application | Threading |
| Thread Form | UN |
| Internal or External | External |
| Insert Size | 21 |
| Pitch | 20 |
Learn more about Klarna
The Carmex Carbide Threading Insert (Unified, TiAlN coated, 21E20UN) is a versatile threading solution designed for shops that run multiple thread profiles. Built for precision on CNC lathes and milling centers, it delivers consistent performance across the most common threading needs with a single, reliable insert system.
- Five length options: Available in five lengths ranging from 12 mm to 40 mm to match different threading tasks and toolholder setups.
- Wide thread-profile coverage: Designed to cover all common thread profiles with one unified insert family.
- Double‑sided cutting edges: Each insert features two cutting edges for extended use; note exceptions for BSPT, NPT, NPTF, American Buttress, and API RD profiles.
- Internal & external threading compatibility: For many profiles, the same insert can machine both internal and external threads, reducing tool changes (exceptions apply for ISO, UN, NPSM, UNJ, and Acme).
- TiAlN coating: TiAlN coating enhances wear resistance and heat tolerance for longer tool life and stable thread quality.
- Carbide construction: Precision-ground carbide provides strong rigidity and consistent thread geometry across cuts.
- Part number: 21E20UN for precise identification and ordering.
This single insert system helps you simplify tooling, minimize downtime from tool changes, and maintain repeatable thread quality across a wide range of profiles. The combination of dual cutting edges, robust carbide substrate, and TiAlN coating translates to reliable performance in both light-duty and heavier threading operations. Ideal for job shops, contract manufacturers, and maintenance environments that require flexible, dependable threading capabilities without juggling multiple insert types.
| Application | Threading |
| Thread Form | UN |
| 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 - Unified - TiAlN Coated
View full collection →You are viewing 21E20UN. 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 Viewing | 21 | 20 | £35.22 | In Stock | |
| 21E24UN | 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 |
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