I created these because one of the pieces I had bought from the store was leaking, and the store was closed at the time. The o-rings for the the part were rubbing in a spot causing them to tear. I redesigned this by changing the placement of the o-rings and the problem was solved. I figure while I was at it I could model the other parts and be able to print the fittings whenever I needed to. I should note that these parts should be printed with ABS due to the fact that they will be outside.
You can download these for 3D printing https://www.thingiverse.com/thing:5366773