Rear Side Fairings (set of 8)These aerodynamic fairing panels are designed to help direct the air more smoothly around the back of your semi truck trailer, helping to further reduce the drag caused by the vacuum air pocket. These panels are the same used in our aerodynamic rear tail fairing for the top of the trailer. Each is designed to fit between the hinges for the back door. 4% increased MPG when installed on the rear top (see above) and both sides of trailer Aerodynamic