This is a basic ball lock connector post for homebrew keggerators. It is intended to be used for cleaning of lines. I wouldn't trust it for water tightness or food safety. I use mine with a simple pond pump and cleaning solution to clean my beer lines on my keggerator.

The part comes in two pieces and is meant to be glued together. I used ABS for the part and ABS glue to weld them together.

I find the post is very tight on my connectors. It might benefit from cutting the groove for the o-ring a little deeper. But mine works so I've just gone with it as is. If you improve on this please re-post and share!

The original file is a ViaCad file. I've also included DXF and STL files.