I bought it because of the unbearable heat of the last week of summer. I did not expect a "wow" effect, but I thought that it would help to reach the first cold weather somehow. There is a USB cable in the kit, through it you can charge and use the fan portablely or connect it to your device via a wire (I connected it to a laptop). There are 3 speeds: the very first was enough for me. The second and third speeds are very powerful for such a small fan, but very noisy. Definitely will continue to use :)