ARTU USA 02964 Diamond Hole Saw, 1-3/8-Inch Diamond hole saw with 3/16" porcelain plus pilot bit, for use on all types of porcelain tile up to a scratch hardness of 8. Can also be used on granite and marble. The unique wave design allows for easier hole entrance and smoother cutting. For best results, cut holes at 400 to 600 RPMs using a liquid coolant. Features Cut holes at slower RPM using a liquid coolant. Bit provides a great pilot hole. Includes hex arbor. Unique wave design. For use on all types of porcelain tile up to a scratch hardness of 8. USA SHIPPING estimates delivery times and we work to get your item to you as quickly as possible and within those times, but please know it may take slightly longer than the estimate.