ROCKBROS Q4 Intelligent Brake Sensing Vibration Sensing Bicycle Tail Light Rear Bike Light IPX6 Waterproof Cycling Accessory The bike's rear light has five modes to switch: 1. Red Slow Flash 2. Red Strobe Flash 3. Breathe Flash 4. Red/Blue/Purple Switching Strobe Flash 5. Red Steady On. Five modes for your choice,improve the safety of riding while also enhancing the fun,making you different in the crowd Easy to install,no extra tools needed,can be easily taken with you so it doesn't get stolen IPX6 waterproof design makes it work well even you get caught in the sudden rain,meets daily cycling needs,do not recommended soaking in water or liquid for a long time ABS body,lightweight and compact,durable and anti-drop,PC optical lens and COB light beads keep the light bright and not dazzling Vibration sensing design allows for automatically waking up the tail light and it will turn off after 30 seconds when sensing no vibration With intelligent brake sensing,the taillight lights up after a brake to warn the rear car Specifications: : ROCKBROS Model: Q4 Material: ABS+PC Waterproof grade: IPX6 Lamp beads: COB lamp beads Weight: yue'deng'yu23g/Pc Mode: 5 lighting modes/3 brightness adjustment Battery life: high light/8-16h,medium light/15-30h,low light/25-50h Package included: 1 x Tail Light 1 x Bracket 1 x Fastener Strap 1 x English and Chinese User Manual Other items not included