1937-62 Chevy 216,235,261 6 cylinder headers. The flanges are one piece, 3/8" thick laser cut steel to eliminate warping and ensure proper mating of the intake manifold and header. They use all the original hardware and include a pair of collector flanges to make attaching your exhaust as easy as possible. We offer them in either a high temp painted finish or metallic ceramic thermal barrier coating, and now polished 304 Stainless Steel.