Well thats a yes and a no sir. It is not a true passthrough. It always runs off the battery so you need a little charge in there. You can however vape as you charge. I'll try and find Morandir Sirs technical review for you and post again.
That's ok RoccoV, no need to search. I'm sure I can find it and what you say makes since. I used the battery once down to zero and once I plugged it in, it didn't work for about 5 minutes until that little charge was achieved. That's why I posted the question and why I will never let it die again. I read one of Morandirs posts and that deep charging is not that good for the Zeus.