Cometic BMW M50B25 M52B28 Engine 85mm .040 inch MLS Head Gasket 323 325 525 328 528 290+ Best Tuesday Morning Greetings, Blessings & Quotes. Comprised of multiple embossed layers of stainless steel with the outer layers utilizing a Viton rubber coating. Compressed operating thickness is 0. 040". Cometic MLS (Multi Layer Steel) Head Gaskets provide maximum sealing performance for todays high output engines and require no sealants. MLS gaskets are ideal for both aluminum heads to aluminum blocks and aluminum heads to cast iron blocks. They can withstand the shearing force created by the two materials. MLS gaskets have increased strength because they are comprised of multiple layers of stainless steel; which also creates the ability to rebound and resist corrosion. The outer layers are embossed and coated on both sides with Viton (a flour elastomer rubber based material that is heat resistant to 250 C 482 F). 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, which can be varied to accommodate multiple thickness requirements. The embossed outer layers of the gaskets meet the demands of a variety of harsh sealing environments, load conditions, and surface finishes The center or shim layer is an uncoated stainless steel layer which can be varied to accommodate multiple thickness requirements Requires less clamp load creating less bore distortion Conforms load distribution across the sealing area Embossed Outer Layers Coated w Viton This Part Fits: Year Make Model Submodel 1998 2000 BMW 323i Base 1998 1999 BMW 323is Base 1991 1995 BMW 325i Base 1991 1995 BMW 325is Base 1996 1999 BMW 328i Base 1996 1999 BMW 328is Base 1990 1995 BMW 525i Base 1993 BMW 525iT Base 1997 2000 BMW 528i Base 1997 1999 BMW Z3 Roadster