I've got an older KL1 head that I rebuilt a while back (5 years ago - I'm getting old!!). It contains a U bin Lux3 (remember those?!) and a Wiz2 at 917ma.
I'd like to pick up a 17650 to use in place of 2x123 but I've forgotten the specs, specifically min and max Vin. Anyone happen to remember?
And a second question, any guesses which would give better runtime? 1x17650 or 2xR123?