The bi-metal hole saw produces smooth cuts in various materials. The tooth geometry (Vario-tooth design) is ideally suited to glide through the material and create smooth cuts. This hole saw is made of bi-metal HSS (high-speed steel) with an 8% cobalt alloy, resulting in a lower risk of tooth breakage and higher heat resistance for long-lasting cutting performance. This hole saw is suitable for cutting wood, metal, and plastic. The bi-metal hole saw fits all standard adapters on the market. Diameter mm: 76, Diameter inches: 3, Working length mm: 44.