The mountune high-flow cotton gauze panel filter for the Mk4 Focus ST provides an instant improvement in both performance and induction noise and is easily installed in less than a minute.
Each mountune filter is manufactured using a multi-stage process resulting in a great fit and virtually no seepage of frame material into the filtration media producing the maximum available filter area.
i've installed the mountune airfilter in the car and i'm pleased with the result. i don't know if there is difference in power because i have not driven enough with it the fitment is easy just be carefull and be sure that the airfilterbox is nicely and proper closed the delivery was perfect and nicely to follow one small thing a sticker to put on that there is another airfilter is fitted would have been nice
Very easy to fit and immediate improvement in performance