Fancy new flashlight with free batteries for life for $67.13.

I just bought a NightCore D10, which runs on dead AA batteries. Very brightly. Appears to maintain it's 130 lumen max (and has two dimmer levels).

So please give me your dead AA batteries.

Because it has voltage management circuitry to maintain brightness as voltage drops, which happens to make it work on batteries that are drained enough that other stuff won't work on them.

I believe this is very common in modern LED flashlights, some of which are much cheaper.

Also, way better than the CR123A batteries that my old fancy flashlight used, which can cost $2 each (it used 2), so I never wanted to use it.

And thanks to perspicuity for the flashlight obsessed input I needed to make my selection.