Iuno bout the icon.
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Please Note:. Unprotected Versions of the 14500 Battery will fit this device.. Protected versions will not.. We recommend Tenergy 14500 batteries or AW IMR14500 batteries only..
I'm sure it's safe since it's singular and not stacked batteries but I just don't trust unprotected bats. I know a lot out there will disagree but when I'm putting something inches from my face multiple times a day I think it's worth a little extra precaution. Just my 2 copper.
Since most folks use LR attys the Icon met that bill in a small package with IMR batts. LiMn is safer chemistry and does not require a protection circuit. It is far safer to use an IMR batt then LI Ion with a failed PCB