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Carmex Thread Turning Internal Insert - UN (UNC,UNF,UNEF,UNS) - Left Hand - 16IL20UNBMA
SKU:16IL20UNBMA
The Carmex Thread Turning Internal Insert is a precision cutting insert designed for internal threading tasks across UNC, UNF, UNEF, and UNS standards. It’s built to support shops and professiona...
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Material Compatibility
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Specifications at a glance
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Download Cutting Data
| Thread Type | Internal |
| Thread Direction | Left Hand |
| Thread Form | UN (UNC UNF UNEF UNS) |
| Pitch | 20 |
£9.50
Prices shown ex. VAT
5 days estimated lead time
— subject to availability
View Other Sizes →
Free delivery over £50 ex VAT
Secure checkout
14-day returns
30+ years expertise
Pay in 3 interest-free instalments. No extra cost if paid on time. 18+ only.
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Description
The Carmex Thread Turning Internal Insert is a precision cutting insert designed for internal threading tasks across UNC, UNF, UNEF, and UNS standards. It’s built to support shops and professionals—from engineers and buyers to tradespeople and hobbyists—delivering dependable results in a wide range of applications.
- Broad thread standard compatibility: Handles UNC, UNF, UNEF, and UNS internal threads with a single insert, reducing setup time and inventory pitfalls while enabling quick, accurate thread production.
- Left-hand threading readiness: Specifically optimized for left-handed threads, ensuring reliable engagement and smooth cutting action for consistent, trouble-free starts.
- Triangular laydown geometry for stability: The laydown triangular design provides robust support, improving chip control and delivering repeatable finishes even in demanding jobs, which helps extend tool life.
Designed to simplify internal threading, this insert reduces setup time and tool-change downtime, delivers consistent thread quality, and supports a broad range of applications from simple to highly demanding. Its versatility helps streamline workflows in machining, maintenance, and prototyping environments, giving you reliable results you can depend on.
Part Numbers
- Protool Part Number
- 16IL20UNBMA
- 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.
Ask our technical team about this tool
Full Range: Carmex Thread Turning Internal Inserts - Unified - Right/Left Hand
View full collection →You are viewing 16IL20UNBMA. Click any other SKU to view its full details.
| Product SKU | Thread Type | Thread Direction | Thread Form | Pitch | Insert Size | Grade | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|---|
| 06IL18UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 18 | 6 | BMA | £8.90 | 5 days | |
| 06IL18UNBXC | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 18 | 6 | BXC | £13.88 | 5 days | |
| 06IL18WBMA | Internal | Left Hand | W (BSW BSF BSP BSB) | 18 | 6 | BMA | £8.90 | 5 days | |
| 06IL20UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 20 | 6 | BMA | £8.90 | In Stock | |
| 06IL20UNBXC | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 20 | 6 | BXC | £13.88 | In Stock | |
| 06IL20WBMA | Internal | Left Hand | W (BSW BSF BSP BSB) | 20 | 6 | BMA | £8.90 | 5 days | |
| 06IL22WBMA | Internal | Left Hand | W (BSW BSF BSP BSB) | 22 | 6 | BMA | £8.90 | 5 days | |
| 06IL24UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 24 | 6 | BMA | £13.93 | 5 days | |
| 06IL24UNBXC | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 24 | 6 | BXC | £13.88 | 5 days | |
| 06IL28UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 28 | 6 | BMA | £8.90 | 5 days | |
| 06IL28UNBXC | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 28 | 6 | BXC | £13.88 | 5 days | |
| 06IL32UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 32 | 6 | BMA | £13.93 | In Stock | |
| 06IL32UNBXC | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 32 | 6 | BXC | £13.88 | 5 days | |
| 06IR18UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 18 | 6 | BMA | £11.60 | In Stock | |
| 06IR18UNBXC | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 18 | 6 | BXC | £11.60 | In Stock | |
| 06IR20UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 20 | 6 | BMA | £11.60 | In Stock | |
| 06IR20UNBXC | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 20 | 6 | BXC | £11.60 | 5 days | |
| 06IR24UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 24 | 6 | BMA | £11.60 | 5 days | |
| 06IR28UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 28 | 6 | BMA | £11.60 | In Stock | |
| 06IR32UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 32 | 6 | BMA | £11.60 | In Stock | |
| 08IL14UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 14 | 8 | BMA | £13.88 | 5 days | |
| 08IL16UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 16 | 8 | BMA | £8.90 | 5 days | |
| 08IL18UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 18 | 8 | BMA | £13.88 | 5 days | |
| 08IL20UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 20 | 8 | BMA | £13.88 | 5 days | |
| 08IL24UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 24 | 8 | BMA | £13.88 | 5 days | |
| 08IL28UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 28 | 8 | BMA | £13.88 | 5 days | |
| 08IL32UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 32 | 8 | BMA | £13.88 | 5 days | |
| 08IR13UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 13 | 8 | BMA | £11.60 | In Stock | |
| 08IR14UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 14 | 8 | BMA | £11.60 | In Stock | |
| 08IR16UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 16 | 8 | BMA | £11.60 | 5 days | |
| 08IR18UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 18 | 8 | BMA | £11.60 | In Stock | |
| 08IR20UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 20 | 8 | BMA | £11.60 | In Stock | |
| 08IR24UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 24 | 8 | BMA | £11.60 | 5 days | |
| 08IR28UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 28 | 8 | BMA | £11.60 | 5 days | |
| 08IR32UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 32 | 8 | BMA | £11.60 | 5 days | |
| 11IL11UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 11 | 11 | BMA | £8.10 | 5 days | |
| 11IL12UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 12 | 11 | BMA | £8.10 | 5 days | |
| 11IL13UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 13 | 11 | BMA | £10.55 | 5 days | |
| 11IL14UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 14 | 11 | BMA | £8.10 | 5 days | |
| 11IL16UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 16 | 11 | BMA | £10.55 | In Stock | |
| 11IL18UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 18 | 11 | BMA | £10.55 | In Stock | |
| 11IL20UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 20 | 11 | BMA | £8.10 | 5 days | |
| 11IL24UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 24 | 11 | BMA | £8.10 | In Stock | |
| 11IL27UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 27 | 11 | BMA | £8.10 | 5 days | |
| 11IL28UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 28 | 11 | BMA | £10.55 | 5 days | |
| 11IL32UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 32 | 11 | BMA | £8.10 | 5 days | |
| 11IL36UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 36 | 11 | BMA | £10.53 | 5 days | |
| 11IL40UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 40 | 11 | BMA | £10.53 | 5 days | |
| 11IL44UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 44 | 11 | BMA | £10.53 | 5 days | |
| 11IL48UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 48 | 11 | BMA | £10.53 | 5 days | |
| 11IL56UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 56 | 11 | BMA | £10.53 | 5 days | |
| 11IL64UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 64 | 11 | BMA | £10.53 | 5 days | |
| 11IL72UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 72 | 11 | BMA | £10.53 | 5 days | |
| 11IR11UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 11 | 11 | BMA | £10.55 | 5 days | |
| 11IR12UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 12 | 11 | BMA | £10.55 | In Stock | |
| 11IR13UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 13 | 11 | BMA | £10.55 | In Stock | |
| 11IR14UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 14 | 11 | BMA | £10.55 | 5 days | |
| 11IR16UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 16 | 11 | BMA | £10.55 | In Stock | |
| 11IR18UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 18 | 11 | BMA | £10.55 | In Stock | |
| 11IR20UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 20 | 11 | BMA | £10.55 | 5 days | |
| 11IR24UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 24 | 11 | BMA | £10.55 | In Stock | |
| 11IR27UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 27 | 11 | BMA | £10.55 | In Stock | |
| 11IR28UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 28 | 11 | BMA | £10.55 | In Stock | |
| 11IR32UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 32 | 11 | BMA | £10.55 | In Stock | |
| 11IR36UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 36 | 11 | BMA | £13.68 | In Stock | |
| 11IR40UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 40 | 11 | BMA | £10.55 | In Stock | |
| 11IR44UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 44 | 11 | BMA | £10.53 | 5 days | |
| 11IR48UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 48 | 11 | BMA | £13.68 | 5 days | |
| 11IR56UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 56 | 11 | BMA | £10.53 | 5 days | |
| 11IR64UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 64 | 11 | BMA | £10.53 | 5 days | |
| 11IR72UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 72 | 11 | BMA | £10.53 | 5 days | |
| 16IL10UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 10 | 16 | BMA | £9.50 | 5 days | |
| 16IL11.5UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 11.5 | 16 | BMA | £7.29 | 5 days | |
| 16IL11UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 11 | 16 | BMA | £9.50 | 5 days | |
| 16IL12UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 12 | 16 | BMA | £9.50 | 5 days | |
| 16IL13UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 13 | 16 | BMA | £9.50 | 5 days | |
| 16IL14UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 14 | 16 | BMA | £9.50 | 5 days | |
| 16IL16UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 16 | 16 | BMA | £9.50 | 5 days | |
| 16IL18UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 18 | 16 | BMA | £9.50 | 5 days | |
| 16IL20UNBMA Viewing | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 20 | 16 | BMA | £9.50 | 5 days | |
| 16IL24UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 24 | 16 | BMA | £7.29 | In Stock | |
| 16IL27UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 27 | 16 | BMA | £7.29 | 5 days | |
| 16IL28UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 28 | 16 | BMA | £7.29 | 5 days | |
| 16IL32UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 32 | 16 | BMA | £7.29 | 5 days | |
| 16IL36UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 36 | 16 | BMA | £9.47 | 5 days | |
| 16IL40UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 40 | 16 | BMA | £9.47 | 5 days | |
| 16IL44UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 44 | 16 | BMA | £9.47 | 5 days | |
| 16IL48UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 48 | 16 | BMA | £9.47 | 5 days | |
| 16IL56UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 56 | 16 | BMA | £9.47 | 5 days | |
| 16IL64UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 64 | 16 | BMA | £9.47 | 5 days | |
| 16IL72UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 72 | 16 | BMA | £9.47 | 5 days | |
| 16IL8UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 8 | 16 | BMA | £9.50 | In Stock | |
| 16IL9UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 9 | 16 | BMA | £9.50 | 5 days | |
| 16IR10UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 10 | 16 | BMA | £9.50 | In Stock | |
| 16IR11.5UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 11.5 | 16 | BMA | £9.50 | In Stock | |
| 16IR11UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 11 | 16 | BMA | £9.50 | In Stock | |
| 16IR12UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 12 | 16 | BMA | £9.50 | In Stock | |
| 16IR13UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 13 | 16 | BMA | £9.50 | In Stock | |
| 16IR14UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 14 | 16 | BMA | £9.50 | In Stock | |
| 16IR16UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 16 | 16 | BMA | £9.50 | 5 days | |
| 16IR18UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 18 | 16 | BMA | £9.50 | In Stock | |
| 16IR20UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 20 | 16 | BMA | £9.50 | In Stock | |
| 16IR24UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 24 | 16 | BMA | £9.50 | In Stock | |
| 16IR27UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 27 | 16 | BMA | £9.50 | In Stock | |
| 16IR28UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 28 | 16 | BMA | £9.50 | In Stock | |
| 16IR32UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 32 | 16 | BMA | £9.50 | In Stock | |
| 16IR36UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 36 | 16 | BMA | £12.31 | In Stock | |
| 16IR40UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 40 | 16 | BMA | £12.31 | In Stock | |
| 16IR44UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 44 | 16 | BMA | £12.31 | 5 days | |
| 16IR48UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 48 | 16 | BMA | £12.31 | 5 days | |
| 16IR56UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 56 | 16 | BMA | £12.31 | 5 days | |
| 16IR64UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 64 | 16 | BMA | £12.31 | 5 days | |
| 16IR72UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 72 | 16 | BMA | £12.31 | 5 days | |
| 16IR8UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 8 | 16 | BMA | £9.50 | In Stock | |
| 16IR9UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 9 | 16 | BMA | £9.50 | In Stock | |
| 22IL5UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 5 | 22 | BMA | £10.69 | 5 days | |
| 22IL6UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 6 | 22 | BMA | £10.69 | 5 days | |
| 22IL7UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 7 | 22 | BMA | £10.69 | 5 days | |
| 22IR5UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 5 | 22 | BMA | £13.93 | 5 days | |
| 22IR6UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 6 | 22 | BMA | £13.93 | In Stock | |
| 22IR7UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 7 | 22 | BMA | £13.93 | In Stock | |
| 27IL4.5UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 4.5 | 27 | BMA | £15.10 | 5 days | |
| 27IL4UNBMA | Internal | Left Hand | UN (UNC UNF UNEF UNS) | 4 | 27 | BMA | £15.10 | 5 days | |
| 27IR4.5UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 4.5 | 27 | BMA | £19.64 | 5 days | |
| 27IR4UNBMA | Internal | Right Hand | UN (UNC UNF UNEF UNS) | 4 | 27 | BMA | £19.64 | 5 days |
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