A single 21700 battery
Regarding battery safety, we advise all users to check their batteries after every use for any rips, dents, tears, scratches, discoloration, or any suspicious marks. If you have any doubts or concerns, stop using immediately. We are not responsible for any damage caused by battery misuse. When not in use, we remind you to carry your batteries in a battery carry case, offered for free at both our locations. If you have any doubts about the quality of your wrap, please take advantage of the free battery re-wraps available at both our locations.