BMW fan clutch wrench is used to remove and install the thermo-viscous fan on BMWs and Fords (32 mm opening) Mercedes-Benz Fan Clutch Holding Tool is used to remove/replace thermo-viscous fan coupling with the radiator in place Mercedes-Benz fan clutch holding wrench holds the water pump pulley to allow release of the fan BMW fan clutch holding wrench holds the water pump pulley in place while loosening the radiator fan