... compact, attractive design, take no space. Indoor Negative Ionizer with Filter Installation: Plug in the power socket, If the LED light ... attractive design, take no space. 3. Built in a dust collector, convenient for cleaning.4. Soundless operation, no motor.5. Save energy only ... as dust, pollen, fuzz and fungal spores. There is no need to replace filter material at all. To clean the collector, simply ...