Description Reviews Milltek Header w/High Flow Cat for MINI Cooper S Traditionally thought of as a downpipe combined with a new higher-flow header (manifold) all mated up to a new Platinum-coated 200-cell German-made catalyst. A 1-2-3 punch for big performance. The stock manifold/downpipe/cat is the biggest bottleneck in your exhaust system. An easy bolt-on installation that comes with all needed hardware & gaskets that need replacing. Removes the pre-cat for higher flow. Can be installed with your stock exhaust or with a Milltek Sport unit (or any other aftermarket exhaust). Look at the difference between the stock and Milltek unit and you will SEE why you will now make power with Milltek. Note: Not legal for on road use or use in California. For off road use only. 1 Review 5 Milltek Header w/High Flow Cat Posted by Nathan Dorsett on 27th May 2020 Excellently built, not coated in anything, atm getting painted and putting a ceramic coat on top, bought for my 06’ Mini Cooper S, takes out the precat, the high flow cat has noticeably larger ports in the lattice inside, very satisfied with the product!