I purchased a Dovpo M VV and would like to use a Sub Ohm tank with it. It's a variable voltage mech mod with safety features so I thought it would be ok to put a Sub tank on it but thought I should check with more knowledgeable people first. Any advice would be appreciated.
Are you talking about this box?
If so, yes it's okay. This is not a mechanical mod, if you saw it labeled that way, the label was wrong. This is a regulated mod, regulated via potentiometer (the little wheel at the bottom.
What's dangerous is putting Any atomizer without a protruding 510 pin on a mechanical mod with no 510 pin, some call them hybrid top mech mods. In that case the 510 of the atty touches the battery directly - and if the pin doesnt stick out past the outer threading, it will cause an instant hard short.
Tl:dr yes it's safe, that mod is not a mechanical mod anyway, thank you for being safe, vape on