Hole saw is made of HSS high speed steel, durable and practical for impact resistance, wear resistance. Hole drill bit is through a special heat treatment, sharp edge, high precision, smooth cutting and high strength. Openings for stainless steel, 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.