 It's powered by USB or by plugging it into the wall. So it's highly portable, in other words. And then where it really shines, the way I use it, it's an odor eliminator. So it gets rid of litter box odors, pet odors, smoke odors, frying odors, musty odors. It wipes out those odors. I've stayed in hotel rooms that had fireplaces in them, and the hotel used them in the room to get rid of the smoky odor. It just, they work. They really do work. I travel with one. I've got one in this hotel. Haven't had to use it. It's a great hotel.