Both genuine miniprotanks 3 and aerotanks V1, and of course their clones, have their bases in nickel chromed brass and some slight parts (base threads) actually are in touch with the e-liquid.... despite their intentions covering them with silicon or PTFE washers or o-rings. Not a big problem though, as long as you check them periodically....
If concerned about brass leeching lead, there is a way to pickle the brass to take care of that. I remember seeing this a while back, but couldn't remember where, so some kind folks on the Reos forum came to the rescue. Here is my thread, Might be helpful to you.: http://www.e-cigarette-forum.com/forum/reos-mods/620404-looking-particular-thread.html
Well, that 'new' info is much appreciated, but I was talking about a simple safety: just a quick inspection of the wet threads made in nickel plated brass to discover the yellow-orangish tell-tale color of naked brass.... and then discard or substitute the now faulty base.
I do not have any intention of using naked brass, even if it is so naked that even surface pollutants have been removed, to get wet my e-liquids and then inhale their vapours.... So once the nickel plated got worn, a new one would be required... Metallic or oxidized copper, and zinc to a less extent, are out of my diet....
Of course, as stainless steel is becoming a de facto standard to make vaping hardware, this will become obsolete sooner or later. Maybe they will manufacture SS bases for their initially brass-machined bases... I think that Aerotanks V2 and beyond (and all its family exceptuating Genitanks) actually are fully SS.
And here in Spain we catalogue those pieces of hardware as "consumibles", i. e. consumables, so they are not intended to endure much. Perhaps it is a blot from the truly disposables CE4, anyway the best Nautilus or Aerotank cannot win in an longevity run against a true rebuildable like a Kayfun, Taifun, Fogger, Squape, et al. They also cost much less (mega-turbo-experiments aside....).


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