Planet Bike Beamer 5 Headlight 5 Nichia 5mm LEDs provide steady and flashing modes FL1 Tested - Run times: 32 hrs (steady  15 lm) and up to 100 hrs (flashing - 15 lm) Side cut outs provide 220 of visibility Water resistance rated to IPX6 standard 2 AA batteries (included) Extra-bright bike light with 5 white Nichia eXtreme v2.0 LED bulbs 4 times brighter than many earlier LED lights for brighter illumination Easy-to-use Quick Cam bracket mounts, adjusts, and removes in seconds Offers flashing and steady modes; runs for up to 100 hours on 2 AA batteries Fits 25.5 to 31.8 mm handlebars; backed by limited lifetime warranty