OpenSCAD customizable port for passing cable through a wall. This can be customized to fit practically any wall whether its 1/2 inch thick or 2 feet. Each half of the port is 75% the thickness of the wall, so there is 25% overlap when you slide the two side together. There are two options, one for a round brim and one for a square brim with rounded corner.

Options are:

Wall thickness
Hole Size
How much of a brim you want. You can use the brim to attach to the wall via screws or glue or double sided tape.
Fit tolerance. Make it loose or really tight.