Wide Range of Applications---Universal chainsaw clutch puller can be used for clutch maintenance or flywheel nut removal or leaf feeder maintenanceMain Function --- This clutch tool is a piston stopper for maintenance, needed to hold the crankshaft in place. The ends are machined all the way around to prevent damage to the top of the piston veryInstructions for use --- just remove the cover and screw this tool in place and lightly tighten, easy to use and very handy if you are doing your own saw or other 2 cycle jobsEASY TO USE --- Rotate the motor clockwise or counter clockwise. anti-clockwise until the plunger collides with the tool and is ready for use. Note that most chainsaws have left-hand threads on the clutch side.Easy disassembly - just remove the spark plug, screw in the tool and tighten lightly. Remove the spark plug, screw the tool in place and press lightly.