1---5 lighting modes: the clear LED indicators display left turn, right turn, steady red light, breathing red light, red and blue strobe, and double flash, providing a full range of visual warning effects. 2---Wireless remote control: equipped with 4 easy-to-use buttons, the bike helmet remote sends signals for different modes. No need to lift your arm to signal direction, enhancing safety during rides. (Remove the battery insulator from the remote control before use.) 3---USB charging: the bike tail light features a built-in 300 mAh battery, rechargeable via the included USB cable. After 1.5 to 2 hours of charging, it provides approximately 4 to 5 hours of operation. 4---Waterproof design: resistant to rain and wet conditions, suitable for use in rainy weather, making it ideal for outdoor cycling. 5---Easy installation: secure Velcro strap design ensures stability and prevents slipping; no tools required. Installation steps: 1. Clean the mounting area. 2. Remove the protective film and attach the Velcro to the helmet. Features: 40g (1 piece), Color: Black, Blue, Red