I guess I am using the term top cap liberally, to me the tank is acting as a top cap because it screws onto the body of the
pv(battery holder and switch). But to clear things up further, from my understanding the UNIVERSAL strata tank will be everything above the the threads of the battery holder, it will obviously need the male 510 threads added to it so it will be able to work on other devices. I think you may be overthinking this, if David is gonna make a universal version of the strata tank, it most definitely is going to include all the parts that the strata was designed with besides the battery holder and switch since those will already be on the mod that you will be using it on. There are no pictures of the universal version so looking at the drawings of the strata
pv can only tell you so much, of course you will not be able to remove the tank portion from the strata mod and put it on anything other than a P18***. The drawings are of the strata
apv and that tank will only work on that mod or other P18's. When David makes the "all mods" or "universal" strata tank it will have the 510 threads protruding from the bottom instead of threads to screw onto a body. I am pretty sure that David has confirmed that he will be making the universal version so its just a matter of when. If I am wrong about that, please someone correct me.
disclaimer: all that being said, I obviously can not speak for David and do not mind being corrected if anything I said is off base.

Bookmarks