I'm looking for a hard use backup flash light. I currently use a Surefire E1B. I would prefer it to be as small and bright as possible but also rechargeable. I can't find anything brighter and rechargeable that what I'm currently using.
Surefire EDC1-DFT (comes with an 18350), EDCL1-T (using 16340) etc etc?
Malkoff Body gaurd amongst other Malkoff lights?
Any LED E series light (single cell) I've owned can use a 16340 (including your E1B).
Many of the double cell lights can use a 16650 (most current models see a reduced out put on 16650 however).