OLIGHT Seemee 30 bike rear light maximum outputs 30 lumens. Emiting an eye-catching and wide-angle beam that can be seen from 800 meters away. With the ambient light sensor, SEEMEE 30 TL will atuomatically adjust the light mode and output depending on ambient conditions. There is also a low battery mode to ensure the durability and energy consuming. The USB rechargeable feature bring you a convenient experience. Also, the built-in battery indicator will be breathing to remind you that it is charging. Sensitive infrared light sensor built in, automatically change the light mode according to environment. Whether you are daily commuting or urban riding, whether it's night time or daytime, SEEMEE 30 will be your companion on the ride.