Ultra Bright Bike Brake Taillight: A built-in integrated accelerometer ensures accurate brake detection, the rear light will automatically turn to brake modes to warn the car coming from behind when decelerating or emergency braking, great for riding on nights. 4 light modes for your choice: slow flash, breathing flicker, and steady on.BRIGHTNESS: 180-Degree field of view width, visibility up to 150m.its super bright especially you brake and in dim to no light conditions for anyone to see your rear.all clearly visible for night no matter rain or fog, Whether youre running, jogging, walking your dog, cycling, skateboarding, hiking, will keep you safe and secureIP65 WATER RESISTANT: Adopted with aluminum alloy, the braking tail light has a nice touch and awesome appearance. It against splashing water from any angle withstands all adverse weather conditions.USB RECHARGEABLE AUTO ON/OFF: Waterproof bike tail light Support quickly charging, the rechargeable bike tail light can be power by 2A cable. Built-in 400mAh Li-ion battery, the taillight lasting 50 hours running time in full charging of 20-30 minutes.An intelligent sensor provide AUTO ON/OFF for the tail light.Saddle Fit Tube Fit Strap-Install: Our smart rear light offers two different install systems- Saddle fit aluminum alloy system and tube fit straps, whatever you want to put on-saddle or tubes, bicycle or helmet, easy to install in seconds without any tools.