... shutter: aluminiun with coating Cone Fan 50inch: QCHS series Cone fans (horn-cone fans) 1. Reasonable cone designing, low noise, big air ... weight, no distortion, open and close sweetly, prevent backflow of air,4. High-strength more high-gluten strength aluminum-magnesium ... wall type, upright wall type, could satisfy varieties need of differents customers.7. The high efficient and energy-saving motor ...