... , adjust room temperature function TKBHOME Ventilation system U series of one-way flow fan U240M898Specifications :Imported aluminum with zinc ... plate housing, HEPA filters,can filter the dust of 0.03 micron, make the air more fresh. ... without rotting.HEPA filters, can filter the dust of 0.03 micron, makes the air more fresh.The ... 47420/20040/258.5 Ventilation system U series of one-way flow fan