This is brightest with four or more cells but works fine at my back door and as supplemental kitchen illumination with 3Ds in it. If KD still does the cheap 3AA to D adapters, two of those in a 2D will give maximum brightness with obviously shorter runtime. With the usage mine gets (Every time I cook when it is dark and when the assistant is out the back), the 8000mAh LSD Ds need recharging every 4-5 months. With 6 cells the Fusion hits 400 lumens in my measurements. It isn't useful much past 60 feet but it gives plenty of light up to there.
40 metre beamshots - Lots of large pictures for some beamshots.