A heat free system,essential oils are diffused into the air.It will remove dust particules and toxins from the air.It has a light bubbling sound that is very relaxing and the mist that diffuses the oils in the air looks so cool.Its very small and upright so it fits anywhere with no clutter.My favorite essential oil to use is Lemon it makes the house smell so clean and crisp and very calming.The only negative is becuse its small it only runs about a hour so if you want it to last longer without having to refill and start up every hour they sell bigger models but I just love this nebulizer!I also dont want to be using artificial air freshners or those plug ins.Id rather be breathing in something that is healthy for me.