EVO 10 Shark Fin Carbon Vortex Generator w/ Antenna Base 5x6cm. Any large vortices effectively grab the car and try to hold it back as it tries to slip through the air. If the air that makes up the vortex can be "tripped" before it leaves the back of the car, it will make smaller vortices, which will have a smaller effect on the overall aerodynamics of the vehicle.
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