Features: Small wind turbine set. It requires you to assemble your own wind turbine, and you can enjoy the fun of DIY at the same-time. This learning toy is good for curious children to understand the driving principle of the motor and how the propellers rotates to generate wind. Just connect your mobile phone USB to the supplied voltages regulator and place your wind turbine in the wind streams (high wind) to generate electricity. It can be used as wind power teaching experiment. It is very suitable for training students and children hands-on ability. Note: The positive and negative poles alternate. Please find out which side is negative and which side is positive, otherwise it will burns out. Specifications: Material: plastic Motor diameter: Approx.24.5mm/0.96inch Motor height: Approx.34.2mm/1.35inch (including front and rear bearings sleeves) Output-shaft diameter: Approx.2mm/0.08inch Output-shaft length: Approx.13.5mm/0.53inch Total diameter of fan blade: Approx.90mm/3.54inch Blade aperture: Approx.1.95mm/0.08inch Power generation mode: DC-mode Output voltage: 0.1-6V Output current: 0.01-0.3A Rated-speed: 200-6000rpm Package Includes: 1 Set Portable Wind Power Generators note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.