Hole saw is made of HSS high speed steel, with extremely sharp cutter, low consumption and durable with impact resistance, wear resistance. High precision, smooth cutting and high hardness. Openings for iron, aluminum, and various types of pipes. Hole saw creates a hole in the work piece without having to cut up the core material. Hole saw is perfect for Installing Locks, Knobs in Doors and Cabinets in Seconds, which make the job quick and easy. Hole saw works with the ordinary electric drill and is ideal for drilling large diameter holes through Desks, Home Wood, Aluminum Plate, Alloy Plate, Plastic Sheet etc.