The Robert Charles Plain Shank Counterbore is a high‑performance cutting tool designed for precision machining environments. Built for engineers, machinists, and workshop technicians, it delivers reliable, clean counterboring with lasting durability.

• Material: M35 HSS‑E with 5% cobalt for excellent heat resistance, wear life, and sustained cutting performance.
• Shank Type: Plain shank for easy fitment in standard tool holders, ensuring stable and straightforward setup.
• Size & Compatibility: 7/16 cap screw size with a 0.437 inch pilot, tuned for precise alignment in common fastener applications.
• Counterbore Precision: Designed to produce accurate, clean counterbores that seating screw heads flush and consistently.
• Applications: Ideal for precision engineering, automotive manufacturing, and general workshop use where repeatable results matter.

The tool’s cobalt-enhanced composition minimizes wear and thermal deformation during long runs, helping maintain precise hole depths and smooth finishes. The plain shank simplifies tool changes and reduces setup time, so you can focus on accuracy and productivity. With its robust construction and thoughtful sizing, this counterbore supports durable performance across a range of materials and fastener sizes, delivering dependable results project after project.