Air Curtains Are Invisible Air Door, Keeps Interior Of A Clean Room Dust-Free, Stops Entry Of Insects, Serves As Temperature Barrier And Isolates Heating, Cooling & Humidity. Fabricated Out Of Mild Steel Sheet. Balanced Blowers Are Mounted On Strong Inside Metal Frame. Exterior Finished In Enamel Or Hammertone Paint. Wall Or Roof Mountings Are Provided.