... easy-caused in the air.Increase inner room oxygen content and generate healthy negative ion to ... is made of fiberglass, can filtrate small particle with the size less than 0. 0001mm, such as ... Micro computer control, four-lay filter and over oxygen device, with high level, mid-level and low level wind ... , 2hour, 4hour and 8hour, Four-lay filter with triple purify effect, remote control.The surface color ...