The Fein Starlock HSS 175 Saw Blade features the 4" diameter blade and can cut sheet metal that's max thickness is a 20 gauge, plastics, GFRP, wood, glazing compound, brass, and bronze. It also has a circular shape that makes clean, narrow cuts that allow to work flush with the workpiece. The blade also has a Starlock mount, which can fit all popular multifunction tool.