Tile/Glass Drill Bit Set: The drill bit is made of durable hard alloy, and the hardness is higher than that of ordinary drill bit. High wear resistance and longer service life. Wide Range of Uses: The drill bit set is ideal for drilling all kinds of materials, including ceramic tiles, concrete, tiles, brick, wood, plastic, glass, masonry and more. Note: When drilling hard materials (glass, porcelain tile, marble or granite), please use water for lubrication. Drill Bits Included: 4 x 6mm (1/4 inch), 1 x 8mm (5/16 inch), 1 x 10mm (3/8 inch), 1 x 12mm (1/2 inch), 1 x Transparent plastic box for different needs. Please lubricate with water when drilling hard materials (glass, porcelain tile, marble or granite). - Features: The tile cutters are clean and smooth, and the absence of broken edges does not mean that easy shaking positioning increases the opening speed. U-shaped groove design with quick removal of drilling dust, 3-plane shaft ensures the drill bit stays firm and stable in the drill.