DeWalt rock carbide SDS plus hammer bits are used for drilling holes in masonry, concrete, rock and artificial stone, and is guaranteed to set up to 25 percent more anchors than other standard masonry bits. DeWalt builds these bits with a rock carbide tip that maximizes carbon surface contact for an extended bit life. And with the 4-flute design, the bit removes debris as you work for fast, efficient drilling. For added safety, the bit is designed with three flats on the shank that prevent it from slipping back into the chuck, and an innovative tip that reduces walking and increases accuracy.