The Cloud Buddy is essentially a "y" or a "u" I guess is a better description with an extra long tail. The tops of the u are female ends, while the bottom is a male end. I think they are all 18mm but I'm not sure.
So I'm assuming he probably does something like this,
....the one photo I found on google apparently won't link here, and I can't actually find another photo describing it lol. Essentially you're turning the Cloud Buddy Upside down, you're putting your Underdog stem in one of the two female ports, and taking the male stem and plugging it into your Hydratube. And you use that glass stopper for the other female end.
I actually was getting some kicks using my hydratube the other day. No cloud buddy, just packed up the 18 mm NonG and shoved it in the tube, and then just stuck it right on top the Underdog
But, I actually have a question, I see Underdog sells the Silicon Stems still....how are these? One of the few I don't have, was thinking of picking some up.
I also, could always use some more silicon tubing. I have an EVO adapter kit that came with some silicon tubing....my question is, is this roughly the same diameter? I know there is not a "one size fits all" in regards to tubing, but the tubing I got with my EVO looks/feels like the tubing I got on an old box style vaporizer years ago.....looks/feels like the tubing on the SSV....looks like tubing that can be used with the EQ (never used one, just looks like it)...and looks like the tubing on your site
I need some Underbutter sometime
running pretty low, figured I might as well make it a one stop shop kind of deal and pick up anything else I need when I place the order. Just would hate to buy tubing that wouldn't fit, this looks like it would, but figured it would be safer to ask.