Features: Suitable for stone, tile, ceramic, glass, etc. Center positioning drill bit helps cut accurate holes Long Life: Reduced drilling speed, low drilling pressure, and increased use of water lubrication will extend the life of the drill bit Clearance Hole: Diamond drill bits with clearance hole facilitate the entry of cooling water and the evacuation of drilling chips. Facilitates the drilling process Clean and Smooth Cutting: Diamond hole saw creates high-precision smooth cuts without broken edges. White zinc plating on bits maximizes tool life with excellent corrosion resistance Tips: Please use at low drilling speed and drilling pressure. Always work with coolant (water) when drilling. Not suitable for drilling tempered glass, plastic, and wood.; Product Description Description: 1. Smooth and precise finish to lower cutting resistance and drilling pressure, increasing sharpness and water lubrication efficiency. 2. Produces clean, accurate holes in minutes with little or no