Specification working principle: The wind blows the paddle on the generator shaft to rotate, and when a certain speed is reached, the motor starts to generate electricity. The higher the rotational speed, the greater the generated voltage. Note that it typically requires airflow from a device such as a hair dryer to achieve higher voltage output, as natural wind may not provide sufficient force.Micro generator: 1. In strong wind conditions, the motor generates electricity. Without connecting LED lights or other loads, the no-load voltage can reach up to approximately 20V. 2. The motor features a built-in USB socket, allowing direct connection of the included USB light. Other low-power USB devices may not be reliably powered. Charging mobile phones or power banks is not supported, as the unit does not include a voltage regulator module. 3. When equipped with a regulated 5V module, the charging current is approximately 30mA under maximum airflow 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 (for shaft fixation) Material: ABS plastic Weight: Approximately 4.8 grams Installation: Equipped with positive and negative paddles, designed to be securely mounted on a motor shaft with a 2mm diameter. Usage: Lights up when exposed to airflow, or can be installed on a bicycle to generate light while riding. Includes a USB light bulb with a 1-meter USB cable, compatible with power banks for emergency lighting. Product includes: 1 x Micro Wind Generator, 1 x USB Light Bulb