You have the top cap on the 18500 tube (a). Take the cap off, put (b) on it, and put them on (d). That'll fit your small battery (H). add (c) for the big battery (g).
A i put the wrong way round when i took the pic and b sits at the top of a
A is the bit i connect my dripper with an up / down screw
B looks like air flow control
The tube part of A cant split any further, though it looks like it should!
C is just a tube
D is a tube with air holes
E will only fit on D
F will only fit on D
If you take the Atty off, take the top of the nem back off and adjust the connector screw so its nearly all the way out , screw the Atty back on so its flush then do the connector screw post back in so it hits the Atty.
Then undo the bottom switch a bit so there is more room for the battery to move down inside the tube and screw your top cap/Atty back in and then re tighten the switch back up, then you should loose that gap
Hope that makes sense
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