Super Mini USB charger fits 510?

[DeaninSJ]

I found an old Super Mini USB charger. My 510 battery seems to fit the threads, but I didn't plug it in.
Will trying this charger harm my 510 automatic batt? I figure it's worth a shot and iIll have an extra charger if it works and doesn't blow my battery.

[kel1109]

Be careful, it seems like alot of the super minis have a reversed polarity of the post (blu/volcano) a normal 510 battery center post is positive while the threading part is negative. Use a tester while someone blows into the ash cap end of the auto batteries.