The 4000 Series Steel Panels feature heavy-duty steel faces that are welded to a steel frame to deliver superior durability and sound control. The 4000 Series panels are especially suited for "Tall Wall" applications from 24' - 3" (7.39 m) up to 42' - 3" (12.9 m) in height. The advanced curve and diverter track system allows these tall panels to be moved effortlessly thru pre-programmed radius-type intersections.