After years of development, we are excited to introduce six-cylinder exhaust manifolds made by XKs Unlimited. Rather than the original gray iron, these are superior ductile iron, a material known for its temperature resistance and dimensional stability -- both of which should increase the durability of any coating. We offer our manifolds two ways: bare, so you can source the coating of your choice, or with a tough ceramic finish. Ceramic-coated manifolds are first ÒpolishedÓ to yield a relatively smooth surface (a laborious process) and then coated inside and out. This limits heat absorption and ensures more heat simply exits the tail pipes. The coating is rated to 1300 degrees F and carries a lifetime guarantee against corrosion or failure of the adhesion to the manifold. (Any failures will be replaced one for one and does not cover labor. No warranty against damage from abuse, accident, or discoloration over time.) The ceramic finish is dark gray in color and "satin" in finish. It does not have the deep-black, high-gloss finish of porcelain/enamel, so while it is perhaps not for concours competitors, it should last for a very, very long time -- something that cannot be said for porcelain/enamel which typically has a very short lifespan. Downpipe studs included. Purchase gaskets and nuts separately or purchase our 07-1504 exhaust manifold installation kit. It contains all the nuts, bolts and gaskets required to install your new manifolds. One kit required per car.