Key Features Built-in Tail Light: Innovative push-type detachable taillight for improved night riding safety. Brake & Vibration Sensing: High-precision sensor automatically brightens during braking or vibration. Multiple Lighting Modes: Five modes including slow flash, jump flash, fast flash, breathing flash, and constant on. USB Rechargeable: Built-in 3.7V 250mAh battery, 18–110h runtime, IPX6 waterproof. Portable Storage: 0.45L capacity with large opening zipper, built-in mesh pocket for easy organization. Three-Dimensional Support: 3D structure with wear-resistant polyester + POLY material protects items from bumps. Versatile Installation: Strap or bracket style, compatible with most bikes, stable and shake-free. Reflective Details: Multiple reflective strips and logos enhance visibility from all angles. Waterproof & Durable: High-sealing ABS shell, laminated zipper, scratch-resistant material, extends tail bag lifespan. Convenient Operation: Press to remove taillight, auto/manual light modes, light-sensing and vibration wake functions. Practical Details: Embossed logo for texture, quiet in daily travel, tight closure prevents shake, easy to carry and mount.