I had a 3D Maglite I wanted to get better use from. So I followed "Scout 24's" advice and ordered the 280 Lumen Firefly LED Bulb from Adventure Sport Flashlights for $16. This is the best upgrade of an incandescent Maglite for the money you can possibly do. The difference was literally like nite and day. The light output is 3 to 4 times brighter, it is a much better white light and being an LED it will have much longer run time. It is a true drop in bulb. No modifying the reflector or the Collar. It comes with its own collar. Every Incandescent Maglite should have this upgrade...Thanks,mjac