Specification working principle: The wind blows the paddle on the generator shaft to rotate. When a certain speed is reached, the motor starts to generate electricity, and the higher the speed, the greater the power generation voltage. It should be noted that it generally requires the wind force from a hair dryer to achieve higher voltage, as natural wind may not provide sufficient power. Micro generator: 1. When the wind is strong, the motor generates voltage without connecting LED lights or other loads. The no-load voltage can easily reach about 20V. 2. The new motor with USB socket can be directly plugged into the included USB light for use. Other low-power USB devices may not be reliably powered. Charging mobile phones or power banks is not supported due to the lack of a voltage regulator module. 3. If equipped with a regulated 5V module, the charging current is approximately 30mA under peak wind power from a household fan. For a smartphone with a 4000mAh battery, the theoretical charging time would be around 6 days. Length: 18cm Inner hole: 2mm (fastening) Material: ABS plastic Weight: About 4.8 grams Installation: Positive and negative paddles can be fixed onto a motor shaft with a 2mm diameter. Usage: Lights up when exposed to airflow; can be installed on a bicycle to produce light while riding. Includes a USB light bulb with a 1m USB cable, 5 watts, which can be directly connected to a power bank for emergency lighting. Product includes: 1 x Micro Wind Generator, 1 x USB Light Bulb