The light has ten LEDs and a maximum output of 400 lumens; it is engineered for impressive efficiency and runtime, providing the best beam pattern for optimal light dispersion in even the most challenging conditions. Plus, with an impressive 80-hour max runtime, you can rest assured that this light will last as long as you need it to. Offering seven different output modes, including the highly disruptive Daytime Flash that grabs attention and the wide-angle optics providing an impressive 270° visibility range. It features a lightweight yet durable waterproof construction, rigorously tested to IPX7 Waterproofing standards. A versatile mounting system attaches to aero or round seatposts, and the light also features USB-C waterproof charging(cable not included). Look no further, as this cycling tail light delivers unparalleled visibility—during the day or after dark.