Makita engineered the 1/4 in. x 8-1/4 in. Thruster SDS-PLUS Bit with concrete construction and masonry in mind. Combining the highest quality steel and impact carbide, the 711237-A reduces vibration for increased comfort on the job. With central guiding action, Makitaâ€™s 1/4 in. x 8-1/4 in. Thruster SDS-PLUS Bit is ideal for accurate hole starts when drilling concrete and masonry.