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Robert Charles Plain Shank Counterbore M35-HSS-E 5% Cobalt - 3/8 Cap Screw Size - 0.406 Pilot Size
| Cap Screw Size | 3/8 |
| Pilot Size | 0.406 |
| Cutting Diameter | 0.604 |
| Shank Size | 1/2 |
| Overall Length | 5 |
Learn more about Klarna
The Robert Charles Plain Shank Counterbore is a high-precision cutting tool designed for engineers, machinists, and workshops that require clean, repeatable counterbores in a single setup. Built from M35 HSS-E with 5% cobalt, it delivers exceptional heat resistance and wear life for demanding metals.
- Material: M35 HSS-E with 5% cobalt for improved heat resistance, edge retention, and extended tool life.
- Shank Type: Plain shank design for easy fitment in standard tool holders, promoting stable machining.
- Size Specifications: 3/8 cap screw size and a 0.406 pilot size for precise alignment and depth control.
- Application: Optimized for accurate, clean counterboring in precision engineering, automotive, and general workshop tasks.
- Performance: Designed to maintain a sharp cutting edge under high-speed cutting and demanding conditions.
With its cobalt-enhanced HSS substrate, this counterbore delivers dependable edge retention and long tool life, helping you complete precise counterbores with fewer tool changes. The plain shank ensures consistent seating in standard holders, minimizing runout and enabling repeatable depths and clean sidewalls. The exact 0.406" pilot size and 3/8" cap screw compatibility simplify setup with common fixtures and jigs, making it a reliable choice for production runs and individual projects alike.
| Cap Screw Size | 3/8 |
| Pilot Size | 0.406 |
| Cutting Diameter | 0.604 |
| Shank Size | 1/2 |
| Overall Length | 5 |
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: Robert Charles Plain Shank Counterbores M35-HSS-E 5% Cobalt
View full collection →You are viewing 5770-3/8-1/32 OVER. Click any other SKU to view its full details.
| Product SKU | Cap Screw Size | Pilot Size | Cutting Diameter | Shank Size | Overall Length | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|
| 5770-4-CLOSE FIT | #4 | 0.112 | 0.186 | 5/32 | 3 | £33.97 | 2-3 days | |
| 5770-4-1/64 OVER | #4 | 0.127 | 0.202 | 5/32 | 3 | £33.97 | 2-3 days | |
| 5770-4-1/32 OVER | #4 | 0.143 | 0.217 | 5/32 | 3 | £33.97 | 2-3 days | |
| 5770-5-CLOSE FIT | #5 | 0.125 | 0.205 | 3/16 | 3 | £34.76 | 2-3 days | |
| 5770-5-1/64 OVER | #5 | 0.140 | 0.221 | 3/16 | 3 | £34.76 | 2-3 days | |
| 5770-5-1/32 OVER | #5 | 0.156 | 0.237 | 3/16 | 3 | £34.76 | 2-3 days | |
| 5770-6-CLOSE FIT | #6 | 0.138 | 0.228 | 7/32 | 3 | £34.76 | 2-3 days | |
| 5770-6-1/64 OVER | #6 | 0.153 | 0.244 | 7/32 | 3 | £34.76 | 2-3 days | |
| 5770-6-1/32 OVER | #6 | 0.169 | 0.260 | 7/32 | 3 | £34.76 | 2-3 days | |
| 5770-8-CLOSE FIT | #8 | 0.164 | 0.272 | 1/4 | 3 | £35.55 | 2-3 days | |
| 5770-8-1/64 OVER | #8 | 0.179 | 0.288 | 1/4 | 3 | £35.55 | 2-3 days | |
| 5770-8-1/32 OVER | #8 | 0.195 | 0.304 | 1/4 | 3 | £35.55 | 2-3 days | |
| 570-10-CLOSE FIT | #10 | 0.19 | 0.314 | 9/32 | 4.5 | £37.92 | 2-3 days | |
| 5770-10-1/64 OVER | #10 | 0.205 | 0.33 | 9/32 | 4.5 | £37.92 | 2-3 days | |
| 5770-10-1/32 OVER | #10 | 0.221 | 0.346 | 9/32 | 4.5 | £37.92 | 2-3 days | |
| 5770-1/4-CLOSE FIT | 1/4 | 0.25 | 0.382 | 5/16 | 4.5 | £41.87 | 2-3 days | |
| 5770-1/4-1/64 OVER | 1/4 | 0.265 | 0.398 | 5/16 | 4.5 | £41.87 | 2-3 days | |
| 5770-1/4-1/32 OVER | 1/4 | 0.281 | 0.414 | 5/16 | 4.5 | £41.87 | 2-3 days | |
| 5770-5/16-CLOSE FIT | 5/16 | 0.312 | 0.475 | 3/8 | 4.5 | £47.40 | 2-3 days | |
| 5770-5/16-1/64 OVER | 5/16 | 0.328 | 0.491 | 3/8 | 4.5 | £47.40 | 2-3 days | |
| 5770-5/16-1/32 OVER | 5/16 | 0.343 | 0.507 | 3/8 | 4.5 | £47.40 | 2-3 days | |
| 5770-3/8-CLOSE FIT | 3/8 | 0.375 | 0.572 | 1/2 | 5 | £63.99 | 2-3 days | |
| 5770-3/8-1/64 OVER | 3/8 | 0.39 | 0.588 | 1/2 | 5 | £63.99 | 2-3 days | |
| 5770-3/8-1/32 OVER Viewing | 3/8 | 0.406 | 0.604 | 1/2 | 5 | £63.99 | 2-3 days | |
| 5770-7/16-CLOSE FIT | 7/16 | 0.437 | 0.663 | 1/2 | 5 | £85.32 | 2-3 days | |
| 5770-7/16-1/64 OVER | 7/16 | 0.452 | 0.679 | 1/2 | 5 | £85.32 | 2-3 days | |
| 5770-7/16-1/32 OVER | 7/16 | 0.468 | 0.695 | 1/2 | 5 | £85.32 | 2-3 days | |
| 5770-1/2-CLOSE FIT | 1/2 | 0.5 | 0.757 | 1/2 | 6 | £109.02 | 2-3 days | |
| 5770-1/2-1/64 OVER | 1/2 | 0.515 | 0.773 | 1/2 | 6 | £109.02 | 2-3 days | |
| 5770-1/2-1/32 OVER | 1/2 | 0.531 | 0.789 | 1/2 | 6 | £109.02 | 2-3 days | |
| 5770-5/8-1/64 OVER | 5/8 | 0.641 | 0.961 | 5/8 | 6 | £142.20 | 2-3 days | |
| 5770-5/8-CLOSE FIT | 5/8 | 0.625 | 0.945 | 5/8 | 6 | £142.20 | 2-3 days | |
| 5770-5/8-1/32 OVER | 5/8 | 0.656 | 0.977 | 5/8 | 6 | £142.20 | 2-3 days | |
| 5770-3/4-CLOSE FIT | 3/4 | 0.766 | 1.187 | 3/4 | 7 | £211.72 | 2-3 days | |
| 5770-3/4-1/32 OVER | 3/4 | 0.781 | 1.203 | 3/4 | 7 | £211.72 | 2-3 days | |
| 5770-7/8-CLOSE FIT | 7/8 | 0.891 | 1.375 | 7/8 | 7 | £255.96 | 2-3 days | |
| 5770-7/8-1/32 OVER | 7/8 | 0.906 | 1.391 | 7/8 | 7 | £255.96 | 2-3 days |
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