This product confuses me a little. They contain a charge controller, but there is no (direct) way to connect the panel to the controller. There is only one DC/Barrel (and USB) jack on the panel. Two connectors included: pin stem to banana clips and pin stem to cigarette lighter plug. The charge controller only has bare wire inputs. Like it's an afterthought and they expect you to just connect the panel directly to the battery? In any case. I cut off the end of the cigarette lighter and connect a cable. And cut off the end of the barrel and connected the banana clip wire so I could go through the controller. No big deal. easy. strange. The instructions don't mention it at all, if you can figure out what they're even trying to say.