1.This shutter has advantages as simple structure, rain-proof, wind-proof, and easy to installation etc.,
2.with preferable ventilation performance and solid figure. The shutter has usage of rain-proof, ventilation, airstream-adjustment, which can be widely used in work plant for electricity generate, metallurgy, chemical, and Gym, theater, other big-size constructions etc., and its usually used in the vent of the constructions outside wall for the elevator, piping system, and warehouse etc..