Microsoft reccomend a charger of at least 40W (15V 2.6V) for the surface pro. I'm finding that most car socket chargers like this are split between 2 ports, i.e. a 40W charger means 20W per port.
I'm wondering now if I can fit one like this;
View attachment 160065
But struggling to find one that is at least 40W on the USB C and not a cheap Chinese fire hazard