Super Power 48" Unheated Indoor Air Curtain with Magnetic Switch. 2 Speeds, High speed at 1648 CFM, 59dB, Low speed at 1295 CFM, 57dB. Easy-Install 12VDC Magnetic Door Switch Included. Automatically Turn On when Door is Open. AHI/LO/OFF switch to select High/Low speed. 120V 60Hz 350W (0.47HP, 3.65A). Super Powerful Air Stream to Prevent the Fly Insects Getting In. Recommended for Back Doors or Warehouse Gates. Air curtain is a powerful fan that is forcing a high-speed air stream over the entrance to isolate the interior and exterior air environment while blocking 90% of Hot or Cold air, dust, smoke, and flying insects. Air curtains are widely installed at the entrances of the supermarket, theater, hotel, food storage warehouse, residential, etc. High-efficiency motor adopting the technology of German electrical machinery, it runs smoothly with reduced low noise. 2 Speeds of operation ranging from low speed to high speed.