Exhaust Manifold, Rear, Series I and II E-Type, "Bare" Unfinished. 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. (See part numbers CO-18396C and CO-18397C.) Downpipe studs included. Purchase gaskets and nuts separately.