Planet Bike Blinky 3H bike tail light 3 5mm LEDs and built-in parabolic lensing provide steady & flashing modes FL1 Tested - Run times: 8.5 hrs (steady  2 lm) and up to 100 hrs (flashing  2 lm) Provides 120 of visibility plus ScotchliteTM side reflective strips for extra visibility 1 AAA batteries (included) Includes self-leveling helmet mount, seat post and seat stay mounts for multiple mounting options