This is a parametric cable duct for neatening up wiring in electronics enclosures.

I haven't used it yet so I don't have pictures, but I am designing an enclosure for a DIY CNC machine and will be using it in that project.

To use this, screw the tray down to your enclosure backplate. Run your cables through the tray. If you need wider breakouts, use pliers to snip out a side section of the tray. Then snap the lid on top.

The files posted on this Thingiverse page are for a 20mm wide x 100mm long x 20mm high cable duct, but you can create any size you want by changing the variables in this OnShape document:

https://cad.onshape.com/documents/a0c8c326b4f030d25e4ea837/w/e1cdb0b59790bc1939bfb9c2/e/85096ba9409fd270b1a5edac?configuration=Height%3D20.0%3BLength%3D100.0%3BWidth%3D20.0

Then just export the lid and tray as STL's.