The Robert Charles Plain Shank Counterbore is a durable, high-precision cutting tool designed for engineers and workshop professionals who need clean, accurate counterbores. Crafted from M35 HSS-E with 5% cobalt, it delivers superior heat resistance and wear life for reliable performance in demanding work environments.

• Plain shank design: Fits smoothly in standard tool holders for quick setup and stable, vibration-free machining.
• Material: M35 HSS-E with 5% cobalt provides enhanced red hardness and extended edge life under hot cutting conditions.
• Pilot size: 0.138 inch pilot ensures precise hole alignment and consistent counterbore depth.
• Counterbore geometry: Optimized cutting edges produce clean, flat-bottom counterbores with minimal burrs.
• Cap screw compatibility: Sized for #6 cap screws to match common fastener recess requirements.

This counterbore is ideal for precision engineering, automotive assembly, and general workshop tasks where durability, repeatable depth, and a smooth finish matter. The combination of cobalt-infused alloy and a straightforward plain shank supports reliable performance across repeated operations, reducing downtime and finishing steps. For best results, pair with appropriate speeds and feeds and secure workpieces firmly to minimize vibration and maximize tool life.