Feature:1. Three Blade: This glass drill bit set adopts internal, middle and external three balde design, which ensures high efficiency.2. Wide Application: This glass drill bit set is suitable for marble, ceramic tile, wall and other stone.3. Low Resistance: This glass drill bit set possesses large chip removal opening design for lower drilling resistance.4. High Efficiency: The drilling speed is fast, the hole is round and there is no breach, providing high efficiency.5. Please Notice: Please keep adding water when the drill bits are working on the glass or ceramics, which can extend the service life.Specification:Item Type: Tile Drill BitsMaterial: High Speed SteelCutting Diameter: Approx. 25.5mm / 1in Package List:1 xTile Drill Bits1 x Hex Wrench1 x Storage Box1 x Spring