Feature: 1. You can position at 45 degrees firstly, then to drill slowly, and to drill down. 2. The hole opener can be used on bench drills, hand drills and machine tools with drilling functions but not on impact drills. (Do not use the impact function to open the hole) 3. Such kind of hand operated tool is applicable to all kinds of stone, ceramics, vitrified tiles, glass, etc. 4. Furthermore, you shall always add water to cool when punching, which makes working more efficiently. 5. Drilling rate is fast, equipped with long service life, such drill bit is built to strict quality control standards Specification: Item Type: Drill bit Hole Opener Size Product Total Length Handle Length Handle Diameter Working Depth Approx. 12mm / 0.5in Approx. 83mm / 3.3in Approx. 25mm / 1in Approx. 9.4mm / 0.4in Approx. 58mm / 2.3in Approx. 14mm / 0.6in Approx. 83mm / 3.3in Approx. 25mm / 1in Approx. 9.4mm / 0.4in Approx. 58mm / 2.3in Approx. 16mm / 0.6in Approx. 83mm / 3.3in Approx. 25mm / 1in Approx. 9.4mm / 0.4in Approx. 58mm / 2.3in Approx. 18mm / 0.7in Approx. 83mm / 3.3in Approx. 25mm / 1in Approx. 9.4mm / 0.4in Approx. 58mm / 2.3in Approx. 20mm / 0.8in Approx. 83mm / 3.3in Approx. 25mm / 1in Approx. 9.4mm / 0.4in Approx. 58mm / 2.3in Package List: 1 x Hole Saw Drill Bit