Mazda 3 has three boxes on its tail wing.

Hello: Regarding your question, the function of the automobile tail wing is to make the air resistance form downward pressure when the automobile is driving at high speed, so as to offset the lift as much as possible, effectively control the downward pressure of the airflow, and correspondingly reduce the drag coefficient. If the tail wing is installed, the air drag coefficient can be reduced by 20%, but the fuel consumption is not obviously reduced when driving on general roads; On the expressway, when driving at the speed of 120km/h, it can save 4% fuel, and the effect of the automobile tail is obvious. If improper installation will affect the driving stability, many decoration shops in the auto parts market can install the tail wing. For the modification of auto parts city, installing the tail wing will only make the vehicle more beautiful, and will not play a real role in the tail wing. I hope my answer is helpful to you.