Originally Posted by
noglider
I don't know if you would call this a floody light, and I don't even know if I'm qualified to describe lights at all. I bought
this light recently and mounted it to my handlebar. I only used it at night once on a short ride, where there was street lighting. I think it works well, and I think I could use it on an unlit road, though I don't know fast it would let me go. It's only $36, and it uses two CR123 cells.
Are two of those cells like a single 18650 cell?
A single CR123 is 3v, so 2 x CR123 is 6v for your flashlight. A single 18650 is 3.7 nominal volt. Most LED Volt forward are in the 3v range so that means most Led flashlight can run on 18650. However the body size is the issue. Flashlight has spring contact on one or both end and can accomondate the longer lenght of a 18650 but a CR123 is 17mm diameter and an 18650 is 18mm. Those flashlight that were design for CR123 most likely are machined out to fit CR123 only and does not have clearance for the 18mm dia of an 18650.