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Carmex Carbide Threading Insert - UNJ - TiAlN Coated - 21I16UNJ
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | Internal |
| Insert Size | 21 |
| Pitch | 16 |
Learn more about Klarna
The Carmex Carbide Threading Insert - UNJ - TiAlN Coated (21I16UNJ) is a versatile threading solution designed for machinists who work with a wide range of thread profiles. Built to perform in both internal and external threading tasks, it delivers dependable, precision results across multiple applications.
- Thread profile coverage: A versatile collection of inserts that covers all common thread profiles, reducing the need for multiple tools.
- Length options: Five lengths spanning from 12 mm up to 40 mm to match different depths and pitches.
- Pitch range: Capable of handling pitches from 0.5 mm / 32 TPI to 6.0 mm / 4 TPI.
- Double-sided cutting edges: Each insert has two cutting edges for extended wear life (note exceptions for BSPT/NPT/NPTF/American Buttress/API RD).
- Internal/external capability: For many thread profiles, the same insert can machine both internal and external threads (exceptions for ISO/UN/NPSM/UNJ/Acme).
- Coating: TiAlN coating enhances wear resistance and heat tolerance for longer insert life in demanding materials.
- Material: Carbide substrate delivers rigidity, precision, and reliable performance in threading operations.
With this insert, you gain a streamlined, economical tool that supports a broad range of thread forms without swapping to multiple inserts. The double-edged design minimizes downtime by enabling reuse across cuts, while the TiAlN coating helps maintain a sharp edge in higher-temperature work. Ideal for job shops and production environments, it simplifies tooling inventories, speeds setup, and delivers consistent thread quality across UNJ and other common profiles.
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | Internal |
| Insert Size | 21 |
| Pitch | 16 |
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 21I16UNJ. Click any other SKU to view its full details.
| Product SKU | Insert Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| 14I24UNJ | 14 | 24 | £32.37 | 5 days | |
| 14E24UNJ | 14 | 24 | £32.37 | 5 days | |
| 14I20UNJ | 14 | 20 | £32.37 | 5 days | |
| 14E20UNJ | 14 | 20 | £32.37 | 5 days | |
| 14I18UNJ | 14 | 18 | £26.50 | In Stock | |
| 14E18UNJ | 14 | 18 | £32.37 | 5 days | |
| 14I16UNJ | 14 | 16 | £32.37 | 5 days | |
| 14E16UNJ | 14 | 16 | £32.37 | 5 days | |
| 14I14UNJ | 14 | 14 | £32.37 | 5 days | |
| 14E14UNJ | 14 | 14 | £32.37 | 5 days | |
| 14I12UNJ | 14 | 12 | £32.37 | 5 days | |
| 14E12UNJ | 14 | 12 | £32.37 | 5 days | |
| 21I24UNJ | 21 | 24 | £43.03 | 5 days | |
| 21E24UNJ | 21 | 24 | £43.03 | 5 days | |
| 21I20UNJ | 21 | 20 | £43.03 | 5 days | |
| 21E20UNJ | 21 | 20 | £43.03 | 5 days | |
| 21I18UNJ | 21 | 18 | £43.03 | 5 days | |
| 21E18UNJ | 21 | 18 | £43.03 | 5 days | |
| 21I16UNJ Viewing | 21 | 16 | £43.03 | 5 days | |
| 21E16UNJ | 21 | 16 | £43.03 | 5 days | |
| 21I14UNJ | 21 | 14 | £43.03 | 5 days | |
| 21E14UNJ | 21 | 14 | £43.03 | 5 days | |
| 21I12UNJ | 21 | 12 | £35.22 | In Stock | |
| 21E12UNJ | 21 | 12 | £43.03 | 5 days |
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