Multi- Drill Bit Set: Tungsten Carbide Tipped for prolonged life Design: U type slot design with fast drilling dust remove, 3-flats allows drill bit to be tightly and stably in power drill.Cut Perfect Circles Holes: Suitable for glass, ceramic tile, wood, ceramic, stone, concrete, brick, etc. When drilling hard material (glass, porcelain floor tile, or granite), use water for lubrication,Perfect for drilling holes in bathroom tiles, or wall . it drills through the tile or mirror this drill bit will cope with any masonry behind itTbhis product cannot be used for drilling toughened glass and drilling of pure concrete ,When drilling, use only flat drill function, do not use any impact force ,When drilling fragile items, the drilling speed is not too high, the pressure should not be too , so as not to damage the drilled itemsColor: black + silverMaterial: tungsten carbideSize: Blade diameter 6mm 8mm 10mm 12mmPackage Contents: 6pcs * Ceramic Tile Drill Bits