I printed them in ABS but PLA or PETG will be fine, print with a brim.
You will see there is a little connector one line wide at the bottom this tricks the slicer so you can set brim to outside only and not have to remove from the center.
Note, this is not cable management for a Bowden set up. It is cable management for a direct drive conversion.
The author marked this model as their own original creation.