I just picked up a couple of these at WalMart.
Handwarmer
They work pretty well, but the capacity is listed at only 5200mah. I suspect a couple of crap 18650 cells inside. I would like to put good cells in it, increase capacity ot maybe 7000mah with a couple of decent 3500mah cells. But, for the life of me I can’t get them to open!
Has anyone had one of these open?
Matt