OSC Premium New Automotive Heater Core is designed to Original Equipment's form and function. OSC's heater cores are technically advanced and made from premium grade Alcoa Aluminum. The tubes are cadmium plated inside and out to prevent premature failure. OSC does not substitute aluminum coolers in place of "Stainless Steel" plate or "Copper" and "Brass" concentric coolers and we use a die cut gasket to ensure there are no leaks. Each heater core is individually pressure tested and engineered for multi-fit without compromising the look and fit. All necessary fittings or hardware are included in each unit. All units meet Original Equipment's cooler design with copper concentric coolers and plate coolers where originally equipped.