The patented design of the See II Air Foil creates two distinct air flow paths down the rear face of the trailer. The inner air flow is a laminar (smooth) flow which creates a buffer of air between the outer air flow and the rear face of the trailer. The outer air flow is a quicker turbulent flow. This flow creates a downward wind force which makes dirt and snow blow past the inner buffer flow, preventing it from settling on the back of the trailer. As the trailer travels down the road, the resulting dust or snow cloud which gathers at the back of the trailer (and follows it) is whisked down and away from the trailer.