I decided to upgrade my daughters old 2 D cell for emergency car use. The parts fit was spot on. The outcome was so much better then I expected. At 60-70 feet a nice large bright hot spot with ample spill, so much more inproved over factory. Adjustable focus was still there but much improved lighting, the donut hole still apears with over adjustment.
If your on the fence and not sure about upgrading your old Maglite? There is no down side when you get you parts from Lumencraft. FYI include the glass lens and rechargeable batteries, best performance for the dollar.
Did my 2-cell that fits in my camper first and was happy so bought another and did my 3-cell. Much brighter than the incandescent lamp.
i use this with lumencraft's 2x26650 battery conversion in a 4d maglite. it is easy to replace the bulb and battery life is great. it also retains the ability to zoom in and out. it is nowheere near as bright as the new led flashlights that claim to put out 20,000 lumens, but those eat up the 2x26650 batteries after about 60 minutes of use (at least the two i ordered and subsequently returned). i use my flashlight for about 10 minutes total every day when letting the dog out and charge the batteries after about 4 months. i can easily light up trees 100 yards away. the only negative is the light has a slight yellowish green tint.
i think the reviews that say the light is dim are probably using 2d maglites. on his youtube video, lumencraft states that these are made for 3d - 6d size maglites. this bulb will work in 2d, but with diminished light output
My 2 cell maglite was sitting unused since every LED flashlight I have produces so much more light. I installed the 325 lumen Firefly bulb in about 60 seconds and now have another LED flashlight with the high quality of a Maglight. Glad I made the purchase!
Very easy to upgrade. I have now brought my 3 Mag Light flashlights up to current LED lighting standards, with much longer use life. I have 4 & 5 D cell batteries. ??