Abstract: A dispensing device for mounting cakes of air treatment material in air distribution systems has bracket means for securement to an air filter panel and open cups for receiving the cakes secured by coupling means to the bracket means. The bracket comprises mutually slidable elements having integral hooks to engage opposite edge portions of a filter panel, these elements having their overlapping portions secured together by friction catch means. The coupling means preferably includes releasable snap-action fasteners, typically mounted on the cups. The cups are provided with openings to permit air passage about the cakes.