I have used the Nitecore NL 650mah protected batteries in the V10R and V11R without issues. Maybe not the best protected 16340 battery but I do know they fit.
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Well I just went thru my 16340 battery stash. The Fenix 700mah ARB-L16-700 is a protected battery and Is a very decent battery. It also fits without problems and is short for a protected 16340.
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You can read HKJ’s review here: Test/review of Fenix 16340 700mAh ARB-L16-700 (Orange-Black)