DIMENSION: Designed with a 6mm Spear-pointed Tip, the multi material drill bits have a 1/4 inches design that reduces breakout. Length: 70mm, Shank: approx. 3/16 inches. Our spear head drill bits are heavy duty, meant to serve for a very long time. WHAT YOU GET: The package includes 10pcs 6mm glass and tile drill bits and a plastic storage box, easy to carry. The multi construction glass bits are smooth, straight and has an ideal texture APPLICATION: Ideal for drilling ceramic tiles, glass, marble, and mirrors. When drilling hard materials, please use water for lubrication, good cooling can extend the service life of the drill bit. The glass drill bits are typically used with electric drills to create holes in all these cited material TUNGSTEN CARBIDE TIP: The ceramic drill bit feature a Tungsten carbide tip for extended bit efficiency and life. During the process of drilling, the coating rubs away the glass, creating a perfect hole in the material being drilled ALLOY STEEL MATERIAL: drill bits set forged from premium ALLOY STEEL quality, glass drill bits provide smooth, accurate drilling in ceramic tile, marble, mirrors, glass, aluminum, concrete and wood. The durable drill bit must be kept well lubricated for the best possible results. This is most commonly done by running water over the drilling surface