Abstract: An air diffuser is adapted to be fluidly connected to an air duct. The air diffuser comprises a face and a unitary valve assembly. The face comprises a number of openings separated by louvers, which are preferably of a fixed angular orientation. The unitary valve assembly comprises vanes that are rotatably attached to a body by a deformable web that is integral to the valve assembly body and the vanes. The vanes are adjusted by means of an adjustment arm that extends from each vane through the openings in the face. The unitary valve assembly is preferably constructed of a single piece of material that is shaped so that it will attach to the face. The valve assembly is unitary, requiring no assembly except to the face. The deformable webs are sized so as to give a high cycle life to the assembly, and allow the vanes to be fixedly adjusted.