Description:* This glass hole saw needs to be used at a low speed, about 800-1000RPM.* Please start your hole diagonally, make a round trace and then hold drill straight.* In order to prolong the life of this glass hole saw, please work with coolant when processing.* Wide used for drilling glass, ceramics, porcelain, ceramic tile, porcelain tile, limestone, slate, marble, light stone and fiberglass. Specification: * Material: Carbon Steel, Diamond Particles* Color: Silver Tone* Drilling Diameter: 35mm / 1.38-inch* Drilling Depth: 32mm / 1.26-inch* Shank Diameter: 8mm / 0.31-inch* Total Length: 52mm / 2.05-inch Package Content: * 5 x Glass Hole Saw.