15PCS Diamond Drill Bits, Tile Hole Saw Remover Tools for Ceramic Glass, Porcelain, Granite Stone Hollow Core Drill Bit Set 6-50mm

Application Glass Drill Bit,Drill Glass, Tile Bottles, Blocks Jars, Fiberglass Porcelain Tile Ceramic, Slate Mable, Granite Light Stone. How to use it? 1 First of all, make the hole and the marble contact surface to form a state of about 45 degrees, and lightly slowly and slowly down to start the positioning process is not too much force. 2 to be open hole device positioning stability will not run away, slowly flattening the hole to 90 degrees vertical prevail, in the process of opening holes to continue to add water for cooling. Note: 1) Start your hole diagonally, make a round trace and then hold drill straight. 2) Always drill pressure and increased use of water lubrication will extend drill bit life considerably. 3) speed kills: Reduced drill speeds, low drill pressure and increased use of water lubrication will extend drill bit life considerably. 4) Warnings: Not for use on Concrete or for depths beyond about 1/2"; Water is required for lubrication when drilling. Specifications: Material: high-quality steel, diamond dust coating. Surface Material: electroplating. Size: 6 - 50mm/0.23"-1.97". 6mm, 8mm, 10mm, 12mm, 14mm, 16mm, 18mm, 20mm, 22mm, 25mm, 26mm, 28mm, 30mm, 40mm, 50mm. Color: Silver. Quantity: 15 pcs. What's in the Box 1x 6mm/0.23"; 1x 8mm/0.31"; 1x 10mm/0.39"; 1x 12mm/0.47"; 1x 14mm/0.55"; 1x 16mm/0.62"; 1x 18mm/0.7"; 1x 20mm/0.79''; 1x 22m/0.86"; 1x 25mm/0.98''; 1x 26mm/1.02''; 1x 28mm/1.1''; 1x 30mm/1.18''; 1x 40mm/1.57"; 1x 50mm/1.96".