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Carmex Carbide Threading Insert - UNJ - TiAlN Coated - 21E16UNJ
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | External |
| Insert Size | 21 |
| Pitch | 16 |
Learn more about Klarna
The Carmex Carbide Threading Insert - UNJ, TiAlN Coated (model 21E16UNJ) is a versatile, high-precision cutting solution built for professional machining where reliable multi-profile threading is essential. Designed for machinists who want fewer tool changes and consistent results across common thread forms.
- Thread profiles covered: A comprehensive collection of carbide threading inserts that span all common thread profiles to support diverse projects.
- Lengths and pitches: Five lengths from 12 mm to 40 mm, enabling pitches from 0.5 mm (32 TPI) up to 6.0 mm (4 TPI) to match your job requirements.
- Double-sided cutting edges: Each insert offers two cutting edges for extended tool life (except BSPT/NPT/NPTF/American Buttress/API RD variants).
- Internal and external compatibility: For many thread profiles, the same insert can machine both internal and external threads, simplifying tooling (excludes ISO/UN/NPSM/UNJ/Acme).
- Coating and construction: TiAlN coating enhances hardness and wear resistance, helping maintain accuracy and prolonging insert life on demanding materials.
- Model designation: Identified as 21E16UNJ, a reliable choice for UNJ and related threading tasks.
Benefits: This single, well-structured set reduces the need to stock multiple single-profile inserts. Its TiAlN-coated carbide construction delivers durable performance under higher cutting speeds and temperatures, helping you achieve clean, precise threads with fewer passes. The dual-edge design and cross-profile compatibility mean fewer tool changes, lower downtime, and consistent results whether you’re threading internal bores or external shafts. Ideal for shops handling automotive, aerospace, and precision mechanical components where UNJ and other standard thread forms are routine.
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | External |
| 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 21E16UNJ. 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 | 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 Viewing | 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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