This is an 18.8mm hydratube, I use it for the Cloud/Evo personally. Works great for flower and oil using the vapexnail. I like that it uses a tiny amount of water but the frit offers a refreshing amount of diffusion while still leaving flavor. You can also leave the HT on the stand and take out the stopper, and then you can use the piece as a traditional piece and throw on a nail or bowl etc. I got it used from Deadshort. He had it custom made I believe?? Regardless of that tidbit's accuracy, they aren't made any more as far as I know, and I've never seen another. He paid over $220 for it and only charged me $150 for it, so I'm going to return the favor and also ask for $150 and shipping, and I'll cover paypal fees. I'd rather keep the stand, but if it's a deal breaker I'll consider parting with it. The pic's are mine, the videos are DS's. Thanks for looking P.S. there's another mouthpiece not in the pictures but in the videos; it will be included.