Essential Air Purifier - Eliminates 99.7% of Air Pollutants | Advanced HEPA Filtration System for Home | Perfect for Allergy Relief & Cleaner Indoor Air

I have had no problems. It is quiet; the various settings are as advertised, and I assume it is cleaning the air. At least the indicator color band says so. I have other air purifiers going part time in various locations, so the air should be relatively clean to start. I wanted a smaller, more portable unit as well and so purchased this one. It runs plugged into a wall outlet via a USB adaptor (not supplied) and via its rechargeable battery I can no longer get filters for one of my older units, and I plan for the Essential Air to be its replacement. The included owner's manual is written in poorly translated Chinese. I found a much more understandable manual via an online search using "Essential Air owner's manual" as the search words.