·Multi layer valgus large plate design, with good diversion effect;

·During operation, the room will not be occupied, and the sealing and thermal insulation can be excellent;

·The thermal insulation board adopts XPS extruded sandwich board, and the two sides are made of FRP. The overall thickness of the board is 40mm, with excellent high-strength compression resistance;

·The opening and closing mechanism of damper plate is rack opening and closing, with high synchronization and consistent opening and closing angle, so as to ensure more uniform ventilation in the house;

·The door panel size can be customized according to the opening size.