Sciaire Essential Air Purifier has a 3-in-1 HEPA filter. It has a peace of mind filter that auto adjust the fan speed depending on the air quality. When the air is good it will remain in sleep mode. For moderate air quality the fan changes to speed 2 and when the air quality is poor the fan increases to speed 3 for fast improvement. Good with a plasma ion generator to actively clean and efficiently filter indoor air, removing particulate matter. It neutralizes harmful chemicals such as smoke, formaldehyde, and other harmful gases. I especially like that it neutralizes smoke. I can breathe much better. All I have to do is plug it in and it does all of the work for me.