Separate tubes for different size batteries by the looks....
It really makes my blood boil with all these Chinese mods how they can't get a simple thing right! Every nice looking mechanical mod is spoilt by an ego thread or a rounded/chamfered top. Wouldn't you think, by now, that they could make at least one mod that has a "one piece" flat topped top cap (no bloody chamfers) with a simple 510 connector. At most, maybe just a couple of grooves for airflow.Yep it appears to be, but jesus look at the size of the top cap, I mean seriously ego thread on a mech, damn you sigelei you just have to spoil it by doing something stupid to it hehe