Bar"s Leaks Block Seal Liquid Copper: * 1-step formula permanently repairs larger leaks in radiators, intake manifolds and gaskets, heater cores, blocks, heads and freeze plugs * Use on cars, trucks, vans, SUV"s and RV"s * New 1-Step Sealer contains an antifreeze compatible sodium silicate liquid glass formula * Will not harm the cooling system when used properly * Use with all types of antifreeze including conventional green or blue (silicate-based) and extended life red/orange or yellow (OAT /HOAT) coolant