1) Corrugated paper has high intensity structure, corrosive resistance, long service life2) Fine percolating and absorbing water to ensure drip wet the wall3) Specific stereoscopic structure. It can provide the largest evaporative surface for heating exchanging between weather and air4) Outer frame can be alternative of aluminum alloy, Cooling system is with its cooling pad paper. When outdoor dry and hot air is through the wet cooling pad paper, the water of water film will absorb the heat in the air and then evaporate large amount of heat. Thus, the temperature of air going through the wet cooling pad paper is lowered. Through such treatment, the wet and cool air comes in house. After mixing with indoor hot air, exhausted by fans, and during cooling, the waste and dust in outdoor air are cleaned, which increases the amount of oxygen in air, makes indoor air fresher, and improves air quality in working environment.