Since it's rated for about 15A I decided to have a go at an experiment with some parts I've accumulated. Per my own experience, I know that the 12v socket is always live. This should work unless there's a diode circuit that I am unaware of. I have a solar mppt controller that I purchased some time ago that I couldn't find a good mounting location in the engine bay or the passenger footwell. I also purchased 2 solar panels from anker that have 2 usb ports a long time ago for emergencies. Never used them. We all have a ton of usb cables. I made my own usb y-cable. With all male connectors. I then used the female connector, cut the leads & spliced the +/- into the solar mppt controller leaving the connection so that it's easily disconnected from the controller or the panels. I have a male-male 12v socket that I made from parts of others so I can charge a jumper battery if I need to. I scavenged another 12v socket (female) and stripped the wires to put it on the mppt controller. Now I just need to find my usb plug-in amp/volt meter to see what I get from the panel to the charger and compare it to what the mppt controller says it's getting. The anker Panel is just 21W. The usb power cable is maybe a 22 awg wire. However, if this experiment goes well, I'll probably do a custom 60w solar sunshade with some beefier wire gauge. So now you're probably wondering "why?". Well, I have a dash camera that is active 24/7 and I just want to make sure I don't deplete the battery as quickly as I am now. If I don't drive for about 4 days the car's dead. Before I get around to installing my dual battery setup, I will make sure to eliminate any parasitic draw that isn't directly from my cameras.