A supply channel is provided with an air distribution system for vehicles, in particular for aircraft. The supply channel includes, but is not limited to an elongated housing, a hollow profile extending in longitudinal direction of the housing, and at least one air shower that includes, but is not limited to an air inlet and at least one air outlet. A generated surface of the hollow profile includes, but is not limited to a multitude of perforation openings. The at least one is designed such that in a region of the air inlet it rests tightly against the generated surface of the hollow profile. Perforation openings that do not lead to an air inlet of an air shower can be sealed off by an adhesive film or foil that has been applied. The supply channel makes possible variable positioning of air showers along the longitudinal direction of the supply channel.