Specification working principle: The wind turns the paddle on the generator shaft, causing rotation. Once a certain speed is reached, the motor begins generating electricity, with higher speeds producing greater 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, when no LED lights or other loads are connected, the motor's no-load voltage can reach approximately 20V. 2. The unit features a new motor with a 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 due to the absence of a voltage regulation module. 3. When equipped with a regulated 5V module, the charging current is about 30mA under maximum airflow from a household fan. For a smartphone with a 4000mAh battery, the theoretical charging time would be approximately six days. (Note: Market-available products in this category generally cannot charge phones or power banks effectively. Even if some current is detected, practical charging is not feasible.) Length: 18cm [Inner hole] 2mm (fastening) Material: ABS plastic Weight: Approximately 4.8 grams [Installation] Equipped with positive and negative paddles, designed to fit securely on a motor shaft with a 2mm diameter. Usage: Lights up when exposed to airflow; can also be mounted 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 use. Product includes: 1 x Micro Wind Generator, 1 x USB Light Bulb