The DMDR duct mounted drum louver series delivers air with extremely long throws, which makes them ideally suited for installation in large enclosures. They provide both horizontal and vertical air stream control. Controlling length of throw and its direction is made possible by the adjustable drum and vane design. The long throw is adjusted by the louver vanes while air directional control is obtained by rotating the drum. The drum rotation features angular adjustment of the jet. The ability to mount the DMDR directly to spiral or round duct work without the use of costly transition taps makes the DMDR ideal for exposed ceiling installations.