http://www.ebay.com/itm/KEYGOS-KE-1-...ht_4969wt_1139

I got 2 of the keygos being that I bought 2 of these ^^ They were crazy bright!! I ran both on low unless riding in streetlights then I'd bump up to medium. They both have run for 2 hours for me switching intermittently from low to medium. I've never ridden at night longer than that with these lights so I have no idea of their depletion time/mode. Unfortunately one day after a long and tiring ride I lost one somehow, but it was kinda ok because one light is plenty. Two of these things is almost, dare I say overkill. I gave the handlebar mount to my brother who was running some cheap $10 pos thing. He happened to have a tactical led flashlight that has wide/narrow focus capability of unknown lumen that fit perfectly. He was always skeptical of using his flashlight for a bike light but now uses the tactical light exclusively. We both win I guess.