Description Siri Italy 8mm Wet Diamond Drill Bits For Porcelain, Granite, Ceramic Tiles  Made In Italy By Siri. The perfect tool for professional or DIY use. Can be used with a standard electric drill. Always use lubrication (water ), otherwise the diamond core drill will burn. This diamond coated core drill bit removes a complete circle from marble, tiles,granite, ceramic or other. * prices shown are excluding VAT.