I have been using a Princeton Tec 40 light for about 3 years. I use rechargables. Its very bright for its size and cost and waterproof down deeper than you will ever go, and if you experiment with Mag Star bulbs you can make it even brighter. I used a 3 cell Mag star bulb for a while and it was exceptionally bright, but the bulb died after about 30 or 40 hours. I am now running a 4 cell Mag star bulb in it and the rechargables last about 6-8 hours of runtime and the bulb has no problem handling the batteries. Its as waterproof as any light, and with its twist on head, very reliable for cheap. I'm not sure about the lumens, but it has been with me SCUBA diving, caving and in many dark places. I even have a red lens cap for it for special night ops.