Titan Diamond Tools core bits are available in sizes from 3/16 inches (5mm) to 6-1/4 inches (158mm), offering the widest selection of diameters to choose from. The 5/8″-11 shank is designed to fit all North American grinders and provides maximum cutting power for precise drilling, allowing for fast and efficient results. The diamond segments are built to be durable and reliable, making these some of the most durable diamond core bits on the market. They are capable of drilling through tough materials like porcelain, ceramic, marble, and natural stone with ease.Available from 3/16″ (5mm) to 6 1/4 inches (158mm).5/8″-11 thread shank to fit a grinder.Designed for wet or dry drilling.Suitable for porcelain, marble, granite, ceramic tiles and other hard natural stones.13,200 Max RPM.