MULTIFUNCTIONAL SAFETY LIGHT: Easy to install. Lightweight and durable helmet light that can be mounted on almost all helmets. It also can be used as bike front lights, suitable for children's bike, adult bicycle, handlebars, seat posts, dog collars or anywhere SET YOUR OWN LIGHT MODES: 3 light mode options: High (3 hours), Low (6 hours), Strobe(12 hours). You can switch different modes according to your needs and different occasions to get the best lighting experience NO BATTERIES REQUIRED: Built in USB charge port for this helmet light (USB cable included). Please charge it when need, and it will just need about 2-3 hours for fully charged WATERPROOF BICYCLE TAIL LIGHT: The taillight is made of IPX5 rated water resistant material to ensure a safe use in heavy rain