When connected to the photo voltaic panel, the fan can run; and may be used on my own by means of technique of plugging into the computer's USB port. When related to a solar panel, the way the fan works will rely upon the sunlight. When the photo voltaic is irradiated to generate sizzling air, the fan directly rotates to use up warm temperature in time, ventilate, save the effort of pulling wires, and it's more secure and extra convenient. There is not any rechargeable battery in the fan; if you want the fan to work at night, you should utilize the ability pack. Specification: Solar panel chip: Polysilicon Solar panel power: 5W, 6V Panel size: 14/5 Mini fan: Size: 4 inches Power supply: USB plug, 5V USB cable length: 70cm/27 Material: Metal colour: black Package Contents: 1 x Solar Panel 1 x Fan Only the above equipment content, varied merchandise are not included. Note: Light taking pictures and assorted reveals can cause the color of the thing within the photo a chunk different from the genuine thing. The size allowed error is +/- 1-3cm.