Compared a handful of tactical lights with 21700 batteries in this video!
Lights in the lineup:
IMALENT MS03
Wuben TO50R
Thrunite TT20
Nitecore MH25V2
Sofirn C8G
Olight Warrior X Pro
Personally, I would have loved to see how the Convoy M21B/M21F would have fit among these lights 
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