K&N filters have just launched their Gen1 Air box lid modification complete with K&N filter element, bolt on power in a matter of minutes.

TUV approved for Europe, fits lots of applications

Focus Mk2 RS

Focus Mk3 ST250, Zetec S 1.6 & 1.6 Eco Boost, 1.1 Eco Boost

K&N's 57S Performance Airboxes 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 airboxes 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