A couple very thin slices of double stick tape applied to the ProVari top cap would solve this problem.
I had the same issue, especially when using my
kayfun on the ProV, but we have the good aviation grade 3M double stick tape at work and one day I tried it and it worked great.
I had both versions 1 and 2 of the Hippo cap, but the
threads on those things are sometimes (read usually) too tight.
I usually do my e-cig maintenance at the kitchen sink/counter. I couldn't tell you how many times I've lost screws, insulators, etc down the drain. One of these days I'll learn my lesson.
Maybe.
Probably not.