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Carmex Thread Turning External Insert - American Butress - Left Hand - 16EL20ABUTK20
| Thread Type | External |
| Thread Direction | Left Hand |
| Thread Form | American Butress |
| Pitch | 20 |
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The ones our customers buy most.Description
Our Carmex Thread Turning External Insert (American Buttress, Left Hand, model 16EL20ABUTK20) is a versatile cutting tool designed for external threading on a range of workpieces. Built for left-hand threads and American Buttress profiles, this triangular, laydown insert is ideal for both simple projects and demanding applications, delivering consistent thread quality across many standards.
- Broad thread-standard compatibility: Works with the majority of thread standards in use today, reducing the need to stock multiple inserts and simplifying procurement.
- Laydown triangular design for stable cutting: The laydown geometry provides stable cutting action, efficient chip flow, and quick insert changes for consistent thread form.
- Left-hand threading optimized: Specifically oriented for left-handed threads, ensuring correct tool orientation and reliable threading results.
With Carmex's trusted manufacturing heritage, this external insert helps you streamline your threading workflow, minimize downtime, and achieve repeatable, high-quality threads across a broad range of applications—from routine maintenance to demanding production runs.
Part Numbers
- Protool Part Number
- 16EL20ABUTK20
- Brand
- Carmex
- Category
- Thread Turning
Delivery
Free UK mainland delivery on orders over £50 ex VAT. In-stock items ordered before 4:30pm are dispatched the same working day. Full delivery information.
Returns
14-day returns on unused stock items in original packaging. Special-order and bespoke tooling is non-returnable. Read our returns policy.
Technical Support
Over 30 years of machining experience behind the counter. Call 01732 887334, Mon–Thurs 8:30–17:30, Fri 8:30–16:30.
Trade Accounts
Credit accounts, contract pricing and scheduled call-off orders available for trade customers. Apply for an account.
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.



