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Carmex Single Long Carbide Shank Threading Insert holders - For Carbide External/Internal Threading Inserts - SR0021M21C
| Insert Size | 21 |
| Shank Diameter | 16 |
| Shank Material | Carbide |
| Reach | Straight Shank |
| Overall Length | 200 |
| Minimum Bore Diameter | 21 |
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Introducing the Carmex SR0021M21C — a single long carbide shank threading insert holder designed for CNC milling that handles both external and internal threading with precision. Built for long overhangs, it delivers reliable reach and consistent results in demanding machining environments.
- Internal coolant bore: Integrated coolant channel directs coolant to the cutting edge for better chip control and extended insert life.
- Long reach capability: Overall length up to 270 mm (metric versions) / 10.5 inches (inch versions) to access deep features without repositioning the workpiece.
- Carbide shank construction: Rugged carbide body provides rigidity, stable seating, and repeatable threading accuracy across jobs.
- Compatibility with carbide threading inserts: Specifically designed to support carbide external and internal threading inserts for versatile applications.
- Metric and inch versions: Available in both metric (up to 270 mm) and inch (up to 10.5") lengths to fit global machining setups.
- Cost-effective threading solution: A practical alternative to taps and dies, helping reduce tooling costs on high-volume threading tasks.
- Helical interpolation-ready: Optimized for CNC milling with helical interpolation to produce precise threads efficiently.
- Operational guidance for long overhangs: When machining long overhangs, reduce cutting speed and feed rate by 20–40% depending on material, pitch, and overhang to maintain stability and tool life.
The SR0021M21C is ideal for shops that frequently perform threaded features in hard-to-reach areas—think automotive housings, hydraulic components, and aerospace fittings. By combining a robust carbide shank, long-reach design, and integrated coolant, this holder enables faster cycles, consistent thread quality, and simpler inventory management, all while offering a lower total cost of ownership compared with traditional threading taps and dies. Its design supports both external and internal carbide inserts, giving you flexibility across a range of threading tasks without swapping tools.
| Insert Size | 21 |
| Shank Diameter | 16 |
| Shank Material | Carbide |
| Reach | Straight Shank |
| Overall Length | 200 |
| Minimum Bore Diameter | 21 |
| Flutes | 1 |
| Insert Screw | S21 |
| Torx Key | K21 |
| Extension | N/A |
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 Single Long Carbide Shank Threading Insert holders - For Carbide External/Internal Threading Inserts
View full collection →You are viewing SR0021M21C. Click any other SKU to view its full details.
| Product SKU | Insert Size | Shank Diameter | Minimum Bore Diameter | Overall Length | Insert Screw | Torx Key | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|---|
| SR0010K12C | 12 | 8 | 9.9 | 125 | S12 | K12 | £244.88 | 5 days | |
| SR0013H14C | 14 | 10 | 13.2 | 110 | S14 | K14 | £206.38 | 5 days | |
| SR0013J14C | 14 | 10 | 13.2 | 155 | S14 | K14 | £212.78 | In Stock | |
| SR0015K14C | 14 | 12 | 15.2 | 175 | S14 | K14 | £266.10 | 5 days | |
| SR0021K21C | 21 | 16 | 21 | 130 | S21 | K21 | £373.86 | 5 days | |
| SR0021M21C Viewing | 21 | 16 | 21 | 200 | S21 | K21 | £385.32 | 5 days | |
| SR0027S30C | 30 | 20 | 27 | 270 | S30 | K30 | £658.68 | 5 days |
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