Designed with elongated oval grooves, this bit is designed to remove wood shavings from woodworking projects easily and then cool them down effectively. A coolant such as water can be used to prevent overheating during drilling operations. Using high-quality bimetallic material, this product is rust-proof, 2mm thick, more durable, and has a 50% longer service life; it exhibits good corrosion resistance and heat resistance as well. The bi-metal construction provides increased stiffness, making it ideal for users looking for a fast, clean way to cut metal. Zinc alloys are exceptionally durable, corrosion-resistant, and extremely difficult to cut.With a toothed blade, cutting is faster and smoother. It has a set of sharp teeth that give clean, smooth cuts. It is also highly precise, and varies between 43mm to 50mm depending on the size of the hole being cut. There is a warning that this hole saw is not recommended for use on concrete, ceramic tile, or thick metal. It is not equipped with a mandrel and pilot drill.