General description Adjustable Hole Locator Set for Ceramic includes 10 diamond drill bits and additional accessories for precise hole drilling in various materials. This set is designed for versatility and durability, making it ideal for DIY enthusiasts and professionals alike. Technical specifications 10 sizes of diamond drill bits: 6mm (0.23"), 8mm (0.31"), 10mm (0.39"), 12mm (0.47"), 20mm (0.78"), 25mm (0.98"), 30mm (1.18"), 35mm (1.38"), 40mm (1.57"), 50mm (1.97") Material: High-strength carbon steel with nickel-plated coating Adjustable hole saw drill guide with a maximum opening length of 3-1/4" Two modes for movable ball bearings (3 or 4 bearing attachment) Usage Suitable for drilling holes in glass, marble, tile, ceramic, PVC, and other materials For optimal performance, maintain reduced drilling speeds and low drilling pressure Use water lubrication during drilling to extend the life of the drill bit Ergonomic design with large clearance holes for cooling water and debris