Pollen filters ensure that noxious substances, such as exhaust, dust or pollen are filtered from the air and not inhaled by the driver or passengers in the vehicle. Activated carbon filters also bind harmful gases like ozone, nitrogen oxide and sulphur oxides, which are 10,000 times smaller than a human hair. Febi Bilstein Pollen Filters sit firmly in their housings thanks to their custom-fit design while offering high filtration performance and reduced pollutant concentration in the vehicle to maximize the comfort of your journey.