3/8" x 4" x 6", fast spiral rotary masonry drill bit, designed for drilling in masonry, block & brick with a rotary drill, providing fast drilling & long life, double flute design provides fast material removal, carbide head delivers long life in masonry applications, precision manufacturing designed to help eliminate bit walking, high speed mode delivers performance in cordless high speed mode, masonry applications engineered for masonry, block & brick, rotary drilling designed for rotary drilling, not for hammer drilling.