The air purifier intermittently rattles so loudly right out of the box that it woke me up twice in the night.  I tried putting a heavy book on top of it but it did not help.  I need it for my bedroom but it is simply too disruptive to be able to sleep with it in the room.  Disappointed but Wayfair refunded my $ in full which I really appreciate.  It's a pleasure to do business with this company as they back their sales and are very customer oriented!