Since it's slow around here I thought I'd post my plumbing aisle mouthpiece, made out of HomeDepot parts.
There was a fair amount of machining done, like cutting the threaded parts off of a connector and fitting them over a section of PVC pipe. I needed to turn the pipe a bit for the threaded part to fit. The inside of the pipe was also machined for USD ww's to fit, as well. The hose fittings are standard sink tailpieces, and the chrome nuts and gaskets are regular sink parts.
I made a wood form for the bitepiece mount, and after turning a short piece of pipe for the ridge, heated it and fitted it over the form. I cut a slightly offset hole in the main body and glued the parts together with PVC primer and cement.
I am working on another intake hose connector that has a barbed fitting to connect to a manometer hose, so I can check cracking on my regs.