IRWIN Tools 1870543 Impact Performance Series 3/16-Inch X 4-Inch Masonry Drill Bit;

IRWIN Impact Performance Series masonry bits are built for maximum durability and long life with impact drivers. Engineered with a pressed carbide tip with aggressive cutting angles, these durable bits drill fast. They have a one-piece construction that withstands higher torque loads than standard quick-change bits that are built with a two-piece design. These bits have a black oxide finish that resists corrosion and increases the life of the bit, and a 1/4" quick-change shank that's designed to work with impact drivers, as well as reduce slipping in standard drill chucks.