Advanced LED rear light with our custom programmed Alert technology, it features our Wide Angle Optics lens that provides up to 270° of visibility and innovative automatic braking sensor. When decelerating, the light will turn solid like a brake light and then provide a distinct flash pattern once stopped to alert riders or vehicles from behind. The light will then change back to its previous output mode once the rider resumes their ride. Its co-moulded construction is super compact, highly water resistant and boasts 5 LEDs for up to 150 lumens of output. With 11 output modes, including a Daytime Flash mode, its got options for any time, day or night. A versatile mounting system attaches to aero or round seatposts and its micro-USB rechargeable. This is the ultimate cycling taillight for incredible daytime visibility and superior visibility after dark. Custom programmed Alert technology. Wide Angle Optics lens. Co-moulded construction. Highly water resistant. Max. 150 lumens. 11 Output modes. Daytime Flash mode. Micro USB charging.