You could say that they replace the all-glass stems, but I'd still probably want both.
It sounds like you get it. It's a few pieces of glass tubes, held in place by the corks when screwed together, while the bowl is created by two screens that are "smushed" into place by the two smaller glass pieces at the bottom.
Much less confusing than it sounds. If the muses' aren't all up on my balls this afternoon, I'll try to take a series of pics.
Okay, let's break it down here.
Pic 1 - The WCT, all put together:
Pic 2 - The separate compenents:
Pic 3 - The screens in the middle and right corks:
Pic 4 - The left glass tube into the left cork:
Pic 5 - The added middle components:
Pic 6 - The added right components, creating a bowl with a screen on top and bottom, held in place extra firmly by the glass:
Simple, yet ingenious.
The 14/19 mm ones are a bit different. Will have to edit in a pic of them from on FC, as mine are both the "plain" end.
http://fuckcombustion.com/threads/the-hi.4693/page-192#post-625144
http://fuckcombustion.com/threads/the-hi.4693/page-192#post-625162
Good pics here too.