Feature:1. Premium Material: These glass drill bits are made from premium hard alloy material, which ensures good performance for neat hole.2. Stable Operation: These glass drill bits provide fast speed and stable drilling performance, not breaking the border.3. Neat Opening: These glass drill bits can create neat, smooth and accurate opening with no broken edges.4. Wide Application: These glass drill bits provide smooth and accurate drilling in ceramic tiles, marble, china, mirrors and glass.5. Using Tips: Remember to add water to the materials while cutting or drilling to preserve them from over heating.Specification:Item Type: Glass Drill BitMaterial: Hard AlloyShaft Diameter: Approx. 6mm / 0.24in, Approx. 5mm / 0.20in, Approx. 4mm / 0.16in, Approx. 3mm / 0.12inProduct Specification: Approx. 10mm / 0.39in, Approx. 8mm / 0.31in, Approx. 6mm / 0.24in, Approx. 5mm / 0.20in, Approx. 4mm / 0.16in, Approx. 3mm / 0.12in.Scope of Application: Hole Open for Glass, Ceramic, Ceramic Tile, EtcWeight: Approx. 54g / 1.90oz.Package List:6 xGlass Drill Bit