Indeed a passthrough is a must have item as well as 12v Adapter. Try to get both of them if you can Susden, then you can give your batteries a break and enjoy
vaping at 5v.
Now if you have a cell phone, go on road trips with the kids etc. I would get a 2 port USB 12v Adapter over at Radio Shack so you can also have your cell phone or laptop or tab plugged in.
Please let us know how you like vaping at 5v.....