Cometic MLS Gaskets are compromised of multiple layers of stainless steel due to its increased strength, ability to rebound and resistance to corrosion. The outer layers of the gaskets are embossed and coated on both sides with Viton- a flourelastomer rubber-based material that is heat resistant to 250 degreesC/482 degreesF. Viton is designed to meet the demands of a variety of harsh sealing environments, load conditions, and surface finishes. The center or shim layer is uncoated stainless steel layer, which can be varied to accommodate multiple thickness requirements. Ideal for aluminum heads to aluminum blocks and aluminum heads to cast iron blocks withstanding the shearing force created by the two materials.