Our car charger is really really old. We charge it off house current and it holds the charge for about 5-6 charges of the phones. The Apple-type compatible connector is white and has 2 USB ports in it
for Apple and non Apple devices. We use it in the 12 V access port on the front.

We do have a dual converter plug in for the car.... so it has 2 plugs which have different voltages. I think that is what you are referring to?

The car charger battery I was referring to is a jump starter carry along not connected to the car, but has a 12V plug to run small things off. That is going on 15 yrs old now and really I think its life is almost over. This was designed for camping use where the car is not available or to jump start a dead car battery.

We wanted a new power source other than the "car jump starter" gizmo..which is quite heavy and a pain to lug around etc. It takes about 12 hrs to charge, and we have to take it to the marina and leave it overnight --weather permitting.

So far this solar device is looking very handy. I hope it holds up and doesn't die-- like so many solar devices reviewed on Amazon that I read. We'll just have to see.