PTFE Tube Holder for MMU2 filament control

Use this to attach the PTFE tubes from the MMU2 to the body of the [MMU2 filament control](https://www.thingiverse.com/thing:3184377). This allows placing the filament control away from the MMU2 unit itself, and gives easy access to each strand of filament.

Stick the end of the PTFE tubes connected to your MMU2 into the holes in the block. You can then load the filament from the spool into the top holes of the final_body, and into the back of the holder. Once you load the filament into the MM