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Carmex Internal Multiple Threading Insert holder - For Carbide External/Internal Threading Inserts - SR0063C21-5
| Insert Size | 21 |
| Shank Material | Steel |
| Reach | Shell Type |
| Overall Length | 50 |
| Minimum Bore Diameter | 63 |
| Flutes | 5 |
Learn more about Klarna
The Carmex Internal Multiple Threading Insert Holder is a precision tool designed for CNC mills to efficiently machine internal threads using indexable carbide inserts. Ideal for shops seeking reliable, cost-effective internal thread milling with quick insert replacement.
- Internal threading holder: Mill-Thread tool holder engineered for internal applications and internal thread milling on CNC milling machines.
- Multi-insert capacity: Accepts 4–8 inserts per holder to extend cutting coverage and reduce tool changes.
- Carbide insert compatibility: Designed to work with multi-tooth carbide inserts for robust, high-speed cutting and efficient chip evacuation.
- Internal-only design: Specifically optimized for internal threading operations, ensuring precise engagement and consistent results.
- Model and compatibility: Part number SR0063C21-5 for traceability and integration with existing milling setups.
- Cost-effective tooling: A cost-efficient alternative to taps and dies, lowering overall tooling costs while maintaining threading quality.
This holder empowers you to tackle a wide range of internal thread milling tasks with confidence. By leveraging multiple carbide inserts, you can push for higher cutting speeds, extend tool life, and minimize downtime through selective insert replacement—delivering consistent thread quality across jobs without the need for specialized taps and dies.
| Insert Size | 21 |
| Shank Material | Steel |
| Reach | Shell Type |
| Overall Length | 50 |
| Minimum Bore Diameter | 63 |
| Flutes | 5 |
| Spigot Diameter | 22 |
| 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 Internal Multiple Threading Insert holders - For Carbide External/Internal Threading Inserts
View full collection →You are viewing SR0063C21-5. Click any other SKU to view its full details.
| Product SKU | Insert Size | Overall Length | Minimum Bore Diameter | Flutes | Spigot Diameter | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|
| SR0063C21-5 Viewing | 21 | 50 | 63 | 5 | 22 | £407.52 | 5 days | |
| SR0063C30-4 | 30 | 50 | 63 | 4 | 22 | £407.52 | 5 days | |
| SR0080D30-4 | 30 | 55 | 80 | 4 | 27 | £438.84 | 5 days | |
| SR0080D40-4 | 40 | 65 | 80 | 4 | 32 | £438.84 | 5 days | |
| SR0100D30-4 | 30 | 60 | 100 | 4 | 32 | £461.54 | 5 days | |
| SR0100D30-8 | 30 | 60 | 100 | 8 | 27 | £509.50 | 5 days | |
| SR0100E40-4 | 40 | 70 | 100 | 4 | 32 | £461.54 | 5 days | |
| SR0100E40-6 | 40 | 70 | 100 | 6 | 32 | £313.54 | 5 days |
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