Feature: 1. Hole Saw Drill Set: Including 6pcs hole openers and 2pcs positioning center drills, with different specifications, which can meet more use requirements. 2. Sawtooth Design: The top sawtooth of these hole saws, high accuracy high frequency welding, ensure incisive cutter teeth and fast drilling speed. 3. Fast Chip Removal: These hole openers are equipped with multiple chip slots, fast in drilling and not easy to block, and suitable for drilling various hard stones. 4. High Speed Steel: The hole saw is made of high speed steel, with high temperature quenching, small incision resistance, neat openings, non fragile edges. 5. Easy Operation: The drilling shall be continued after the central drill is used for positioning, so as to prevent the drilling deviation, stable and reliable. Specification: Item Type:Hole Saw Set Material: High Carbon Steel, Diamond Center Drill Size: Approx. 7mm / 0.28in, 9mm / 0.35in Hole Opener Size: Approx. 25mm / 1in, 28mm / 1.1in, 38mm / 1.5in, 44mm / 1.7in, 70mm / 2.8in, 73mm / 2.9in . Package List: 2 x Drill Bits6 x Hole Openers1 x Wrench1 x Plastic Box