Product size about : 10*7.5cm/3.9*2.9 Product color: As shown in the figure Battery capacity: 200mah Weight: 65g Battery life: 8-12 hours Product material:ABS product features: 1. Personalize your bicycle with a customizable two-digit number display from 00 to 99, allowing you to showcase your identity, team affiliation, or favorite numbers for a standout look on every ride, making it fun and unique for cycling enthusiasts. 2. Enhance your nighttime safety with three distinct illumination modes: high brightness for maximum visibility in dark areas, medium for balanced light during dusk, and a flashing mode to alert others effectively, ensuring you stay safe and visible on road rides. 3. Enjoy hassle-free operation with an easy clip-on installation that requires no tools, and a memory function that saves your number setting automatically, so you can quickly turn it on and off with a simple button press for convenience. 4. Ride with confidence in any weather thanks to its water-resistant design, which handles rain, splashes, and humid conditions without issues, making it all your outdoor cycling adventures. 5. Power up efficiently with a fast-charging Type-C port, offering long battery life that lasts for hours on a single charge, so you can enjoy extended rides without worrying about running out of power. Precautions: 1. As we all know , the different computers display colors differently, the color of the actual item may vary slightly from the following images. 2. If you feel difficult to choose the size, you can contact us at any time. We will give you some suggestions, but for your reference only. Shipment includes: 1 pc Bicycle rear light