Package Included: 1 x Diamond Hole Saw with Center Drill Bit: Hole diameter 1"(25mm), Total length 2-3/4"(70mm). Excellent Design: The diamond hole cutter is made of high-hardness industrial-grade carbon steel; the surface is chrome-plated to enhance corrosion resistance; high-quality diamond coating improves sharpness and cutting speed; center-positioning drill bit improves cutting accuracy. The combination of these features results in smooth, fast and precise cuts. Extended Service Life: During operation, please keep adding water to keep cool and increase lubrication, reduce drilling speed and pressure, which can greatly prolong the service life of the hole saw. (Please note: dry drilling is strictly prohibited with this product.) Widely Used: Suitable for glass, tile, ceramic, marble, slate, granite and other light stone materials. Not suitable for concrete and tempered glass.