Partstock(TM) Bicycle Cycling Laser Tail Light Water Resistant 2 Laser & 5 LED 7 Modes Mountain Bike Safety warning Flashing Lamp Alarm Light Back Rear Led. The 5 LED & 2 laser beam bicycle safety light creates a virtual lane around your bike, helping to protect and keep you safe from incidents during night-time cycling or in the dark. The laser bike light is the perfect accessory for keen cyclists or anyone with safety concerns or worries about the dangers of cycling at night after recent stories of car and bicycle collisions in the news. 7 Modes of flash mode: Always bright, flash, slow flash, left to right, right to left and left to right slow flash, flash, flash back and forth. The laser bike light works for up to 36 hours and has a simple, tool-free application allowing you to be safe and secure on the roads in very little time. Powered by: 2 AAA batteries (batteries NOT included)