These are mostly enlarged Voron 0.1 handles. I replaced the magnets with holes for the regular M6 screws which are used throughout the build and also made the ends a bit thicker.
Kudos to the Voron team for such a great design ( https://github.com/VoronDesign/Voron-0/tree/Voron0.1/ )
I printed them with 40% infill and it should work without a brim as the model doesn't tend to warp.
The handles are using the same hole distance and size than the nylon handles RR ships with the enclosure so you can use the standard holes.
Update March 2022: I enlarged the handles and forgot that this also meant that you will need M6x20 instead of M6x16 screws. M6x16 will barely grip the nut so you may use that as a temporary solution.
The author remixed this model.