Green Leaf Plug-in Negative Ion Travel Portable Air Purifier (BLUE) Negative Ion output: 3*10^6 pcs/CM^2 (Non-adjustable). (RED and BLUE purifiers produce Negative Ion, ORANGE AND GREEN purifiers produce Ozone Ionic) Chemical Free: does not use or produce chemicals. Low Power Consumption. Compact Design: Ideal for small spaces in Homes & RVs. Easily moved and portable Purpose: Remove smells; prevent bacterial infections; fresh air; increase the air oxygen content Application: Bedroom, study, office and meeting room. Purifies up to 322 sq. ft. Quiet Operation & Low Maintenance