Multiple Layers Steel (MLS) head gasket. Direct replacement – this Head Gasket Set are designed to match the original gaskets required to reseal and restore proper function on specified vehicles. Restores functionality – this Head Gasket Set are made to fit and fully restore part functionality after the original gasket fails. Durable construction – this Head Gasket Set are made from quality materials to ensure reliable performance and long service life. Trustworthy quality – These Head Gasket Set are designed for the professional installer. It does not come with any installation instructions. If you do not have a service manual, please consult a professional mechanic prior to installing this kit. Purpose of Head Gasket. Correct operation of the engine requires that each of these circuits do not leak or lose pressure at the junction of the engine block and the cylinder head. The head gasket is the seal that prevents these leaks and pressure losses. A leak in the Head Gasket – often called a “blown head gasket”. Head gasket leaks are classified as either external or internal. External Leaks:oil or coolant on the outside of the engine (typically underneath) are visible. Internal Leaks: when the fluids enter another circuit and may result in changes to the coolant or oil. Full Gakset Set, Head Bolts. OE Spec or Performance/Custom. Kit or Single Part.