This Aaria Humidifier is a humidifier and air purifier in one. No need for two separate  devices in your home. The weather this past week has been super cold so our furnace has been running nonstop.This humidifier has really helped with the dryness in the air. It has 3 fan speeds with a night mode. I've only just started taking advantage of the air purifier feature. It says its HOCL technology actively  kills 99.9% of airborne viruses. We can really use that with all the flu going around our community. I'm not sure if that's true, I hope it does. I know I have some peace of mind thinking it does.