Abstract: An inflatable rear fairing to reduce drag incident to highway speed movement of box like trucks and trailers. The invention attaches, in one or more sections, to the rear door(s) of the vehicle and when inflated form an apex at its rear, to minimize the wind resistance of the vortex which normally forms at the rear of a square backed truck. The invention flattens, when deflated, to allow easy access for loading or unloading the vehicle.