Bar’s Leaks Radiator Stop Leak Concentrate, No.1196, is designed to stop minor cooling system leaks and drips caused by normal cooling system wear and age. The formula works with all types and colors of antifreeze, coolant, and/or water. It stops and seals coolant leaks, in addition to sealing leaks in radiators, gaskets, heater cores, and freeze plugs. One bottle covers the cooling system of most 6- and 8-cylinder passenger vehicles and light trucks, while half a bottle can be used for 4-cylinder engines.