DT DIATOOL Hex Shank Dry Diamond Drill Core Bits 2PCS 12mm Vacuum Brazed Hole Saw for Tile Porcelain Ceramic Marble Granite

2 pieces diameter 12mm vacuum brazed hex shank dry diamond drilling core bits Diameter: 12mm; Diamond length: 10mm; Total length: 80mm; Hexagon Shank; Maximum drilling depth: 30mm Wax inside for cooling, dry drilling without water for granite marble masonry concrete tile ceramic When drilling, the wax will melt to lubricate and cool the drilling surface Applying excessive pressure will not make the bit drill faster but will create excessive heat and subsecuently reduce the efficiency and life time