ive gotten a few of the extended 510 batterys..usually lasts me atleast 5 hours. so big improvement. my usual tool is a GG trans...at 6 volts. just went to indyvape today for the first time today (pretty damn cool he said it was one of only 5 in the damn country, i assume he doesnt mean the idiots selling at mall kiosks)...shocked he had high resistance attys for it. i killed several 510s when i first got it.