Mitsubishi Electric Air Curtain Residential and Light GK-25/30 Series Air Curtain - GK-2509-3012AS1-CE are the perfect way to provide your premises with a comfortable, clean and hygienic environment while saving energy with a quiet, efficient and powerful operation. The air curtain not only insulates temperature efficiently (i.e. preventing loss of cool air during cooling and heat loss during heating) it can protect your premises from unpleasant elements found in the external environment.