Bi-metal blades feature a toothed edge made from high speed steel (HSS) attached to a flexible steel backing through an electron-beam welding process. This configuration results in a blade that makes precise cuts while resisting breakage. They are used on ferrous and nonferrous metals. Straight-backed blades are used for cutting straight edges. The cutting surface of a toothed edge is composed of a row of pointed teeth. Common tooth variations include the number of teeth per inch and pitch pattern. They are used on ferrous and nonferrous materials. Size 9”. 10 TPI. Blade width 3/4”.