battery I believe... I don't have them yet, they on the way, hence the 10 day auction.... I'd guess probably not the most perfect time keeping but it's more of a necklace / decoration than for it's time keeping!
pretty long, I'll measure when I get home.... probably hangs down below your rib cage, but that's the style apparently.... see my dragonfly necklace listing, the pix there show a longer chain, my guess is it is as long as that one