1. The function of this ventilator is to keep the inside and outside pressure to be balanceable, even the inside temperature is under 0°C, so as to ensure free open of the door.

2.With a temperature controller inside the window, which keep the window’s temperature within 20°C-40°C, then guarantee fluent ventilation. With a stainless steel filtrating net, which prevent the insect from entering.

3.Groove on the surface, avoid the inleakage of watere.

Ac 220V or AC 110V are on your option.