Sports Biking 5 LED + 2 Laser Tail Light with Early Warning Laser projection - Waterproof Taillight with 3 modes - Batteries Included and Easiest Installation 5 LED Ultra-Bright Weather-Proof Taillight with 3 Modes to Maximize Battery Life 100-200 Hours Battery Life(Depending on LED Mode) 2 High Powered Lasers with Ground Projection for Early Warning Very Simple Installation Batteries, Seat-Post Mount included