K&N

K&N's 57S Filter element only, is supplied with a rubber bung which once removed increases waste gate turbo chatter noise! it can be easily replaced if you require a quieter driving experience. Focus Mk2 RS - fits with standard Airbox or with standard Airbox fitted with mountune Airbox lid or J1 Airbox lid Focus Mk3 ST250, Zetec S 1.6  & 1.6 Eco Boost, 1.1 Eco Boost AutoSpecialists sale price, RRP £92.50 our price £89.95  K&N Performance FILTERS increase horsepower and acceleration by dramatically reducing air flow restriction caused by the original factory design. They come with K&N's Million-Mile Limited Warranty. 57S series air-filter replace the factory air filter housing with a fully enclosed injection modified air box containing a reusable K&N air filter. Installation is easy as they are specifically engineered to use factory holes and mounting points. No additional hardware, cutting or drilling is required

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K&N's replacement air filters are designed to increase horsepower and acceleration while providing excellent filtration. We make over 1,200 different replacement air filters for the majority of vehicles on the road. These filters are washable and reusable and are custom designed to fit into your existing factory air box. Their drop-in design means adding performance is simple. With most vehicles you simply remove the disposable air filter and replace it with a K&N. See applicable instruction sheet for details. Designed to boost horsepower and rate of acceleration. Can be cleaned and used again. High air flow with exceptional filtration. Lasts up to 50,000 miles before cleaning is required depending on driving conditions. Works with original equipment manufacturer vehicle electronics. Emissions legal in all 50 US states- Will NOT void vehicle warranty. Our stock replacement air filters for street vehicles are covered by our famous K&N Million-Mile Limited Warranty and will be the last air filter your vehicle will ever need.Million Mile Limited Warranty®

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