K&N Replacement Air Filter (33-2873) Ford > Focus > Mk3 2010-2018 > ST250 2010-2015 and the spring can be

and the spring can be replaced to match the boost of tuned cars

Increased surface area of filter

The intake diameters on these air intakes have been carefully tuned to provide exactly the correct quantity of air ensuring solid consistent power gains throughout the rev range without any loss of low-end torque

2 x 40mm Hose Clamps

K&N Replacement Air Filter (33-2873) Ford > Focus > Mk3 2010-2018 > ST250 2010-2015 and the spring can beK&N washable, reusable High Flow Air Filters feature a state of the art design of layered, oiled cotton media engineered to improve airflow and capture contaminants, and are designed to provide an increase in horsepower. Each performance air filter is reusable, engineered to last for the entire lifespan of your vehicle, and backed by K&N's No Hassle Lifetime Limited Warranty. K&N drop in replacement filters are designed to install easily into your