I didn't get the Foxy Box mods VV because I knew I wouldn't want to have to mess around finding the perfect carto for all the variable voltages so I got the FBM 5V and put a 2.0 DCC on it. These are sorta new and I found them at SweetVapes. I'm getting great flavor and tons of vape. The 3.0 single coils are good on it but these 2.0 DCC's are something else. Steve has all 3 of his mods in stock at foxyboxmods.com.
That's really not how it works. You find the voltage for the juice and carto you are using. You don't go buying cartos for different voltages unless you are wanting to try something different.