Features: 1. Charging design: USB charging for long battery life, breathing light mode, battery life up to 6-8 hours, constant light mode can also be used for 2-3 hours. Silicone seal, dual protection, waterproof, dustproof, durable, waterproof, and rainproof (please don't soak in water) 2. Ultra-sensitive intelligent sensor: When the light shakes or the wheel rotates, the light turns on by itself and then turns off automatically after 30 seconds. It saves worry and effort. The light is strong during the day, and the light is not turned on. It is environmentally friendly and energy-saving. Touching button design. 3. It is more convenient to operate, more durable than physical buttons , and has better waterproof performance. Long press for one seconds to turn on, short press to switch the light mode, and then long press for one seconds to shut down. 4. Gifts: These bicycle wheel lights will be perfect birthday gifts and Christmas gifts for boys, girls, teenagers and adults. Make it the focus of attention on the road to make driving at night safer. 5. Quick installation: No tools are required for spring buckle, easy to disassemble and assemble, firm and durable. First, press the spring buckle to turn on the hub lamp, then stick a thick and moderate gasket on the inner side, and then puts it on the wheel hub to close, the installation is complete Notice: 1.Actual color may be slightly different from the image due to different monitor and light effect 2.Please allow 1-3cm deviation due to manual measurement Description: Weight: 60g/each Suitable shaft diameter: within 30MM Process: Ultrasonic Light mode: 37 kinds includes: 1x Bicycle Wheel Hub Lights