I think it's just a power adaptor......plug it into your cig lighter and it can power different electronics e.g. portable radios, small televisions, cd players, that kind of thing. It wont do anything else except give power to electronics.
that won't be able to hook up to an ipod at all. the charging system for the ipod is through the usb adapter and i doubt that has usb on it. plus like comp said, it's just for power. theres no link between that and your stereo.