Beat the elements and add some attitude to your Truck, Van or SUV. Sidewind Deflectors allow you to keep your windows partially open, to provide ventilation to the interior. Today's modern aerodynamic body styles with form fitting doors and windows no longer feature rain gutters to channel away water. The result is usually water dripping into the interior. Sidewinds act like a drip - edge for your vehicle, this allows you to keep your window partially open for ventilation, without the rain getting in. As air flows around the outside edge of the sidewind it creates a small low pressure area underneath it (much like an airplane wing) which creates suction to keep out the wind and draw out the stale air from inside your vehicle.