CarGo copper reinforced "Liquid Glass" METALLIC SEAL-UP is the only permanent block, head, and radiator sealer that uses copper fines in the formula. The copper strengthens the bond and transfers heat across the hole or crack to eliminate hot spots. SEAL-UP is ideal for gasoline and diesel engines.  SEAL-UP will with stand temperatures up to 2000ºF and 3000 pounds per square inch pressure. A SEAL-UP ceramic-metallic seal is as permanent as a "hot weld" and will last the life of the engine or radiator. A  bottle of CarGo # 1008  will treat up to a  6 gallon cooling system & permanently seal your cooling system.