It is safe even if there is no power from take power from the PC if I use the USB cord provided. Most suitable for the use of the desk. Lightweight, because it is compact size, I can carry easily anywhere around the house. Batteries (single 2 x 2 sold separately) By using, there is no need to worry about annoying outlet. aroma is on the wind of the fan just drip 2-3 drops of water aroma oil of your choice (sold separately), you can enjoy aromatherapy easily . Use two single form two batteries with warranty tank / 250ml power / USB bus power or (cable included), (sold separately) 130 x 100 x 150mm, weight: Body: 280g, treasuring: 400g