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Carmex Twin Threading Insert holder - For Carbide External/Internal Threading Inserts - SR0030J21-2
| Insert Size | 21 |
| Shank Diameter | 25 |
| Shank Material | Steel |
| Reach | 52 |
| Overall Length | 108 |
| Minimum Bore Diameter | 30 |
Learn more about Klarna
The Carmex Twin Threading Insert Holder is a versatile indexable tool designed for CNC thread milling. It supports carbide external and internal threading inserts and is optimized for threading jobs performed with helical interpolation on CNC mills. The twin-insert design helps you complete threads faster while keeping tool changes to a minimum.
- Twin-Insert Design for Fast, Efficient Threading: Two threading inserts in the holder increase material removal and throughput, reducing cycle times on CNC mills.
- Internal Coolant Bore for Cleaner Cuts: An integrated coolant channel delivers coolant directly to the cutting edges, improving chip evacuation and protecting inserts during long runs.
- Cost-Effective, Indexable Thread Milling Solution: Replaces costly taps and dies with replaceable carbide inserts, helping lower tooling costs while preserving high-accuracy threads.
By using the Carmex Twin Threading Insert Holder, you gain reliable, repeatable thread milling performance with less downtime and lower tool cost. The twin-insert design maintains consistent cutting action across runs, while the internal coolant bore supports longer insert life and better surface finishes. For shops seeking to streamline threaded work on CNC mills, this holder delivers fast setup, versatile compatibility with carbide inserts, and a dependable platform for high-precision threading.
| Insert Size | 21 |
| Shank Diameter | 25 |
| Shank Material | Steel |
| Reach | 52 |
| Overall Length | 108 |
| Minimum Bore Diameter | 30 |
| Flutes | 2 |
| Neck Diameter | 24 |
| 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 Twin Threading Insert holders - For Carbide External/Internal Threading Inserts
View full collection →You are viewing SR0030J21-2. Click any other SKU to view its full details.
| Product SKU | Insert Size | Shank Diameter | Reach | Overall Length | Minimum Bore Diameter | Neck Diameter | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|---|
| SR0020H14-2 | 14 | 20 | 41 | 93 | 20 | 16 | £190.84 | In Stock | |
| SR0030J21-2 Viewing | 21 | 25 | 52 | 108 | 30 | 24 | £234.06 | 5 days | |
| SR0040L30-2 | 30 | 32 | 70 | 130 | 40 | 30 | £275.40 | 5 days | |
| SR0050M40-2 | 40 | 40 | 78 | 153 | 50 | 38 | £318.64 | 5 days | |
| SR0020C14-2S | 14 | M8 | Head Type | 48 | 20 | N/A | £190.84 | 5 days | |
| SR0025D21-1S | 21 | M10 | Head Type | 60 | 25 | N/A | £140.66 | 5 days |
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