Cabin air filters are very efficient: During only one hour of driving, an air volume of up to 100,000 liters is circulated through the vehicle interior. All the more important is regular change of cabin air filter elements. MAHLE recommends changing the cabin air filter every 15,000 km or a minimum of at least once per year. If the cabin air filter fails or is clogged, the pollutant concentration in the interior of the vehicle can increase to six times of that of the outside air. MAHLE cabin air filters reliably supply the driver and passengers with clean air to breathe, which safeguards their health, well-being and ability of the driver to concentrate even in the event of smog or high pollen count. They also reduce the load on the blower, protect heating and air conditioning from contamination, improve air circulation and prevent dangerous fogging of the windows. In addition, the inside of the windows and fittings remain cleaner for longer.