... Air flow range: 150-1200m3/h, wildly used in large and medium-sized meeeting room, office, hotel room, hospitallization building, ... room, edible mushoroom farms, chess room, dining, shopping malls and so on. 2. Ultra-low running quiet performance, concection core ... 3. DC brushless unit noise reduction 2-5dB than ordinary models, quieter and room quieter, which the lowest operating noise only 28dB ...