100X 6mmMarble Ceramic Glass Brick Tile Porcelain Drill Bit Hex Shank Spear HeadFeatures: Full grinding and anti rust treatment, clean and sharp without burrs . The drill bit is more wear resistant and more durable. Small incision resistancefeature drilling stably, fast speed, not breaking the border. Opening neat, smooth, no broken edges, no tremor phenomenon, chip easily. Professional glass and tile drill bits provide smooth and accurate drilling in ceramic tiles, marble, thin iron plate, mirrors and glass. Remember to add