Wind deflectors for side doors are an important element of car accessories. They enable natural exchange of air inside the vehicle. They prevent windows from fogging on rainy days, since they allow ventilation of the car interior. When the window is open, wind deflectors protect the driver against the direct impact of gushes of wind. They decrease dirt on side windows, enabling better view in wing mirrors. They make it possible to open windows even during heavy rain or snow. They highlight the style line of the vehicle. The picture presented here shows an example of fitted side wind deflector. Heko is the leading Polish producer of wind deflectors for passenger cars that has customers all over the world. Side door wind deflectors for light commercial vehicles and trucks are very popular among professional drivers. It allows control over the airflow through the driver's compartment. Such wind deflectors are particularly appreciated during difficult weather conditions (high temperatures, rain, snow). They decrease the risk of getting ill due to strong local overcooling of the body.