I believe the Kanger Subtank line got cloned quite a bit over the years, much like the Vision Novas before them. That compounds some of our fit issues and the packaging is virtually identical.
That's true. But back when I bought my subanks, I didn't buy from China and only bought from vendors who were on Kanger's "authorized vendor" list they used to have published on their site. They were all bought from Madvapes, Lightfire and MVS, all of whom were on that list.
So I believe the problem here is that Kanger was always infamous for consistency. However, despite the differences in chimney lengths, all the tanks fit the Kanger coils & RBA properly.
The problem comes when trying to fit/use a coil head that wasn't designed for the tank. That's when the inconsistencies become apparent (otherwise I'd have never noticed them).
I'm thinking that there's more than just V1 and V2 for subtanks. Probably goes all the way up to V47

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