Note: This tool is required to remove the clutch from certain model saws. You will need this tool to replace your clutch and drive sprocket, or service your oil pump. Each tool has a 19mm nut fitting so you can easily adapt a socket or bar wrench to torque. Crankshafts are left hand threads so too loosen clutch you'll turn in a clockwise motion and counter clockwise to tighten. A piston stop will also be needed to preform this job. NEVER USE AN IMPACT WRENCH!!! USE HAND TOOLS ONLY! OR YOU RISK BREAKING YOUR CRANKSHAFT OR KNOCKING A HOLE IN THE TOP OF YOUR PISTON!