VENTILATOR PORTSP ressure Ventilator:The function of this ventilator is to keep the inside and outside pressure to be balanceab

Pressure Ventilator:The function of this ventilator is to keep the inside and outside pressure to be balanceable,even the inside temperature is under 0oC,so as to ensure free open of the door. 

Balance window YL-220 is square pressure ventilator.

high pressure ventilators