The previous tenant made a lot of holes in the walls to run TV cables. I wanted to tidy them up a bit so I created this super basic wall grommet that includes a flange to hide the mess of the holes.
The holes in your wall should be between 22-25mm. Larger holes up to 32mm can work but will be partially blocked by the flange.
Use a bit of glue on the flange and push into the existing hole.
I'm using these for networking cables (CAT5 ethernet and CAT3).
See it in action: https://www.youtube.com/watch?v=S4HHslZGlHE