I built myself one of these dual 120V adapters (never used it yet for charging), but am now wondering about whether I'll ever use it. I've read a few posts about hotels and RV parks with dodgy wiring, and just yesterday I was doing some more investigation of the electrical set up at the barn I bought a little while ago. Yipes! All sorts of dangerous stuff. So I'm becoming a little more cautious about electrical systems "in the wild".