It's a little bit large for a pocket or every day carry (edc) light, but it's not too big like an old maglite. Comes with an 18650 battery which runs longer than AAs, and recharges in the flashlight. Charge cord included. Just loosen the front end to expose the USB connector. A light in the on/off button flashes red while charging, green when it's done. Mine didn't even get warm, charges pretty quick. I have to tell you there was a problem that went away after playing with the light for a few minutes. When I first got it everything was fine EXCEPT when I got to the flashing selection it wouldn't turn off. I tried everything, then opened the battery compartment (unscrewed back end of light). That turned it off. Replaced battery and after clicking it through the levels and turning it on & off for a few minutes it cleared up. Works fine now. I gotta say it's REALLY BRIGHT! I'll probably use it in my truck, or for camping. Would be good for a boat too, it has O-ring seals.
