“EST” stands for ‘Extreme Sealing Technology’. EST gasket sets include gaskets made from different materials designed to create the best seal for the application:

SPS (Spring Steel) Gaskets are made from embossed stainless steel, coated with a high temperature viton material that virtually eliminates leakage when joining two metal surfaces.

MLS (Multi-Layer Steel) Gaskets are 3-piece head gaskets that include a stainless steel center sandwiched by two SPS outer layers.

AFM (Aluminum Foamet Material) Gaskets have a chemically blown, compounded nitrile synthetic foam-like rubber bonded to an aluminum core. AFM material does not require gasket sealers or silicone bead.

EST gaskets are used in critical sealing surfaces such as rocker box and cylinder base gaskets. Head gaskets included with these kits are Cometic’s ‘MLS’ (Multi-Layer Steel’). The balance of components included with these kits are made from the highest quality materials to ensure that your engine stays leak-free.

Zipper’s Performance stocks most all gaskets, seals and o-rings individually for ’66 and later Big Twins and ’57-up Sportsters®. Contact Us with your specific needs!

Weight 1 lbs

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