Premium Quality: Vacuum brazed diamond technology provides super high efficiency, cuts faster and lasts longer. Filled with cooling wax and suitable for dry drilling. Wide application: for drilling glass, tiles and hard ceramic tiles, porcelain, granite, marble, quartz, limestone , fiberglass, terrazzo, porcelain stoneware, masonry, stoneware. Universal shank: designed with a 6.35 mm hex shank, suitable for the chucks of all standard drills and drills hammer drill bits from Bosch, Hilti, Metabo, Makita, Milwaukee and many more Drill diameter: 6mm, 8mm, 10mm, 12mm Dry drill or use water for longer life. Note: Please use with water when drilling granite. Special function: 1) Filling with cooling wax increases service life when dry drilling 2) Although it is a wax core drill that can be used for dry drilling, when the wax core runs out, it can be cooled with water or coolant while drilling for longer life. Specification: Diameter: 6 mm, 8mm, 10mm and 12mm Hex shank: 6.35mm Overall drill length: 66-80mm Application: 1.) Use the supplied carbide drill bit to create a starting notch. 2.) Now place the diamond drill bit at an angle of approx. 45 to starting notch and drill carefully. 3.) Once the notch is deeper, place the machine and diamond bit in an upright position. 4. ) Slightly circular while drilling, this ensures that dust and dirt are removed from the hole. 5.) Stop drilling and periodically cool the diamond drill bit and the material 6 .) Repeat steps 4 and 5 until you have finished drilling the hole. 7.) Always clean the diamond drill after completing the drilling process and remove all residue before to use it again. Attention: Cordless screwdrivers require a speed of at least 1600 rpm. A speed above 2-3000 rpm is recommended for electric drills. The use of low-power, low-speed machinery reduces Package:4 * diamond cutters