Kryptonite Alley F-800 Front LightFront Light Lumen output at high steady: 800 Compact, sleek design Run time at high steady: 1h30 Robust safety features including daytime and nighttime 6 pulse modes Side illumination ports allow cyclists to be seen when riding across traffic lanes Fully USB rechargeable no batteries to buy or replace Memory function allows light to turn on at the last mode that was used