Now that my flashlight collection is now about two dozen flashlights of various sorts, I’m running into a problem remembering which of my single AA lights can also handle 14500 cells. I’ve noticed that even on just the Sipik 68 and its clones and variants, some can handle 14500 and some can’t. Also, even if I know which light can handle a 14500, how do I keep my wife/kids from putting a 14500 into the wrong flashlight? Do any of you mark/engrave your flashlights to identify what cells can go in them? I wish there were a standard way to tell what voltage range a flashlight is designed for. Right now I only have one pair of 14500 cells to keep track of, but if I buy more, I’m going to have to keep those cells under tight control!