Drill America DEWCBR Series Qualtech High-Speed Steel Counterbore, 1/2″ Shank Diameter, 3/16″ Pilot, 5-1/8″ Length, 11/16″ Size (Pack of 12)

Drill America Qualtech DEWCBR series counterbore. Counterboring is the enlargement of a portion of a hole that has previously been formed. If the counterbored portion is shallow (1/8-inches or less), the operation is usually known as spot-facing; for example, a flat seat for a bolt head or nut. If, on the other hand, the hole is enlarged to a considerable depth, it is designated as counterboring. This counterbore is made of two-piece construction, having an integral shank and counterbore-cutter, and a pilot that is interchangeable, which provides flexibility in the use of the tool. High-speed steel tool is good for most general purpose applications, offering a combination of hardness and toughness for wear resistance. Round shank allow use with a wide variety of toolholding systems.