Built in LED beads, low energy consumption, high brightness, supports 3 flashing modes Make of PP and resin materials, light weight and enduring, suitable for long term use. High brightness windmill lights can significantly enhances visibility at night or in low light environments, ensuring safe riding. The overall weight is extremely light, which will not cause additional burden on the bicycles. After installation, it will not affect the riding speed and handling. Suitable for circular rods with a diameter of 2-2.5cm/0.79-0.98inch. Installation can be completed without any tools, convenient and fast.