It is important to change your impeller every 1-2 years on the Volvos, or they can break apart and end up clogging your cooling system. Utilizes a adapter/reducer and a center bolt to effortlessly pull your impeller without damaging the housing of the impeller. Do not attempt to do this with screwdrivers or other tools. Use this kit for a trouble free install. Be sure to plug your water intake line if changing this while in the water.