Product Description ------------------- The Irwin Glass and Tile Drill Bits are suitable for drilling glass, porcelain and ceramics. Drilling should be carried out using a low RPM (300 RPM recommended) and water cooling is also recommended. The hammer action function should not be used while using these drills. Box Contains ------------ Irwin IRW10507912 Glass & Tile Drill Bit 5 Piece Set 4-10mm Comprising: 4mm Glass & Tile Drill Bit 5mm Glass & Tile Drill Bit 6mm Glass & Tile Drill Bit 8mm Glass & Tile Drill Bit 10mm Glass & Tile Drill Bit