General Tools circle cutters produce precision cricles in sheet metal, brass, copper, soft steel, aluminum, plastic, wood and composition materials. The Wheel and Circle Cutter is the ideal tool for making clock faces, toy wheels, birdhouses and other projects; Great for woodworkers, model builders, clockmakers, and hobbyists. This innovative design features a reversible, double-ended blade which allows the tool to be changed from a circle cutter to a wheel cutter in seconds. The high-speed steel cutting blade makes exact diameter circles from 1” to 6″; Maximum safe speed is 500 RPM, for use with a drill press only, shank is 3/8 inch round. Both the blade and pilot bit are replaceable and remove easily with a hex wrench; Replacement blade is General Tools Model # 6 Blade, replacement drill is General Tools Model # 5/6/55 Drill.