● main application in the ventilation system in the fresh air at the entrance, in blocking the incoming ambient noise, while the full flow of the air; ● stability, fire, any weather, apply non-flammable acoustic filler; ● In general, under the pressure loss of the muffler has a superior performance; ● wing blade separated by a minimum of pressure to maximize noise attenuation, and the leaf orientation separated by a straight line of sight, Yier enhanced aesthetics and acoustic performance; ● weather, rain or snow blocking baffle intrusion; ● a variety of specifications suitable for installation in any size and structure of the linear form of ventilation, "wall" in; ● choose a variety of colors to meet the installation location of the surrounding landscape; ● According to different requirements can choose to galvanized steel, stainless steel or other material.