K&N Stock Replacement Air Filter for Focus SPI/Zetec/SVT/ST170

K&N's lifetime replacement air filters are designed to increase horsepower and acceleration while providing excellent filtration. K&N makes over 1,200 different replacement air filters for virtually every vehicle on the road. These filters are custom designed to fit into your existing factory air box. Their drop-in design means adding performance is simple. Simply remove the disposable air filter and replace it with a K&N; there is NEVER any cutting or fitting required. K&N's stock replacement air filters for street vehicles are covered by their famous K&N Million-Mile Limited Warranty™ and will be THE LAST AIR FILTER YOUR VEHICLE WILL EVER NEED.