The claim is that the light "can come to 1800 lumens." With what batteries, i don't know.
All i have is aaa nimh's lying around so that's all i've tried. I haven't had the light long and i don't ride often in the dark so i don't know how long a runtime i'm getting. I'm using it on my handlebars so I'm not so worried about weight. Just whatever works well and is cheapest.
