All Rugged Ridge designs are extra tough for extreme usage. Flanges are welded 360 degrees to stand up against the hottest conditions. This is a great upgrade for your stock 6 cylinder 4.0L engine. The complete bolt on kit includes manifold, gasket, hardware and down pipe flange gasket. All Rugged Ridge headers come with a limited 6 month/6,000 mile warranty. Compare the value of these extra high quality headers to any other high end header manufacturer.