The Blackburn 2 Fer light is a convenient front & rear combi bike light that can be easily mounted & switch on using a convenient push button. A fully closed unit makes the 2fer waterproof. The 2fer light front & rear combi light has a white front light max output of 60 lumens & 2 light modes that last up to 6hrs, switch to the 2fer rear red light mode to get 20 lumen & 2 light modes lasting up to 9hrs.