Material: PC shell Size: 8.4*2.2*1.4cm / 3.28"*0.86"*0.55" Light color: five colors Light mode: 4 modes 1. High-brightness design ensures significantly improved visibility when riding at night. The wide range of visible light allows vehicles behind to spot you earlier, ensuring riding safety. 2. IP67 waterproof performance, no matter rainy days or slippery road conditions, the taillight can keep working normally no matter what the weather conditions are. 3. Convenient USB charging design, no need to replace batteries, environmentally friendly and economical, one full charge can be used for a long time, reducing the trouble of frequent charging. 4. Equipped with anti-slip rubber straps, compatible with frames of various diameters, stable installation without looseness, ensuring that the taillights are stable and do not fall off even on bumpy roads. 5. The lightweight design will not add extra burden, while the simple and stylish appearance adds a sense of technology to your bicycle. Package Includes:1pc Bicycle taillight