Suitable for processing stone, tile, ceramic, glass and granite, etc. Center pilot bit cuts precise holesLong life: Reduced drill speeds, low drill pressure and increased use of water lubrication will extend life Drill BitClearance Hole: The diamond drill bits together with the clearance hole facilitate the entry of cooling water and the evacuation of chips from the drill. Facilitates the drilling processSharp and Smooth Cutting: The diamond hole saw creates smooth, high-precision cuts with no broken edges. White zinc plating on bits maximizes tool life with great corrosion resistancePlease note: Water is required for lubrication and cooling when drilling. Not for use on concrete or for depths beyond approximately 1/2 inch Product Description Description: 1. Smooth, precise finish to reduce incision resistance and drilling pressure, increasing sharpness and efficiency of water lubrication. 2. Produce clean, accurate holes in minutes with little to no chipping. The pilot bit in the center makes it possible to cut precise holes. 3. White zinc plating on bits maximizes tool life with high corrosion resistance. Excellent for drilling glass or ceramics and greatly extending bit life. 4. The diamond drill bits together with the clearance hole facilitate the entry of cooling water and the escape of chips and other particles from the drilling. Facilitates the piercing process. 5. Suitable for processing stone, tiles, ceramics, glass and granite, etc. Works best with a power drill (not included). Specifications: Material: Diamond, Carbon Steel Features: With Center Pilot Bit Finish: White Zinc Plating Package: 1pcs x Diamond Drill Bit Note for Use: 1. Please always use lubrication (water) when the drill bits are working. 2. Low drilling pressure and increased use of water lubrication will extend the life of the bit. 3. Not for use on concrete or for depths beyond approximately 1/2 inch. Note: Data is manual measurement, please allow 1-163cm error, due to differences between light and screen, there will be a certain color difference, the specific received in kind prevail. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.