QEP's Xtreme Series 1-1/2" (38mm) Diamond Milling Cone is designed to enlarge, shape and round-bevel existing holes in porcelain, hard ceramic, granite and marble. It is manufactured with superior brazed diamond bonding for greater durability and faster, smooth cuts. It can be used for polishing, stone carving, hollow tangent, and trimming. It works with all standard grinders, no adaptor necessary.