On my Mag Lite, 2 and 3 D cell lights I dropped in a TerraLux led "bulb" and use Powerex 11,000 mAh rechargable batterys. The beam will shine 100 yards plus and lights will burn for many hours. I have used these lights for a couple months every night and have not recharged. In my Surefire G2 lights, I also dropped in Cree led bulbs and heavy duty rechargable bats. Will also illuminate 100 yds and in such a small package. The day of paying a couple hundred for a custom made flashlight are gone.
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