The A'PEXi metal head-gaskets provide upgraded protection on high horsepower engines. Factory head-gaskets cannot withstand the pressures of high output operation and often cause the engine to "blow." This condition is actually caused by a failure in the factory head-gasket. A'PEXi recommends replacing the factory head-gasket with a metal one before gasket failure causes more damage to the engine. The gaskets are all designed engine specific and provide a complete and secure seal.