BMW Genuine Supplementary Microfilter Set

Ridged and narrow, the Genuine BMW microfilter vastly reduces the concentration of contaminants and dirt particles in the car's interior, making the air you breath inside the car up to eight time purer than the air outside.
Fed through a water-repellent and chemical-resistant plastic polypropylene fleece, the air is filtered by combined mechanical and electrostatic means. Despite its compact external dimensions, the fleecce contains a staggering total average of 200,000 square metres in surface area, the equivalent of a 5mm wide strip going right around the Earth.