It can control the air direction, so that the airflow screwing in can better mix the air 

Remove dead angle at the air inlet of the wetted pad in longitudinal ventilation 

Three layers of sandwich insulation board (glass reinforced plastic + polystyrene + fiberglass) to prevent energy loss 

Continuous EPDM foam sealing strip can prevent harmful wind and leakage 

Specially designed reinforcement bars can prevent bending deformation, which is airtight 

The upper end of each reinforcement bar is equipped with an adjustable pull arm, so users can adjust the state when the door is closed 

Users can breezily adjust the size of the opening as a whole according to the instructions issued by the environmental handler 

In winter, when completely closed, the thermal insulation performance is more than 8 times that of ordinary shutter, and the heating cost is reduced by about 15% compared with ordinary shutter