For those of you H2 users who are wondering, the tube at the top of this coil head will not fit inside the chimney of an H2 clearomizer. H2 clearos that I have had require a tube that is 3.25mm diameter.
The tube on these are 4mm in diameter.

However, not sure if maybe you could replace the tube on this coil with the one off an H2 clearo. May try that. Weill let you know.