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Dual Emisar DW4 and D2 headlamp mount model to 3D print!
(www.printables.com)
Portable illumination
Rules:
Related:
It's pretty common for cavers I think. I can see the value in having redundancy plus you could angle one of the lights down to have more spill directly in front of you.
Seems like it would be better to stick with lights that use the same batteries though