The DeWALT DW4712B 7", high performance masonry blade is a high quality blade intended for cutting brick & masonry material. It features a 5/8" diamond knock out arbor for a faster cut rate at constant depth which minimizes dust with thinner kerf. It lasts up to 30 times longer than abrasive blades and is for use o n 7" & 7-1/4" circular saws.