There are many parts of your car that were pressed into place using large amounts of force. If one of these needs to be removed -- things like gears or pulleys -- they don't come easy. You need help. You need a gear puller. This 3-jaw version is for stronger jobs. There is also a 2-jaw puller. The three jaws clamp the gear or pulley while the center screw rests in the axis. They work very well.