Edna and Nora are available as a 'lamp only' option, without battery box, for your own creative solutions.
For 3.7v li-ion battery arrangments only. Multiple cells should be arranged in parallel for total volatge 3.7v (not for series wired cells) and incorporate protection circuitry. Lamps are polarity protected, but observe polarity all the same, and over discharge protection for good measure.
Examples could include a Petzl Duo box, which stripped out can accomodate just about accommodate a 1S2P 3.7v li-ion pack, an original Petzl Zoom box, or other battery box recovered from retired caving light. Remember, keep 3.7v li-ion batteries dry or expect to damage protection circuitry etc. Waterproofing li-ion battery packs is essential if using Zoom box!!
Requires a level of skill. Please don't take this on if you are technically challenged !!!