Small PTFE tube guide that I use for the MMU3.  My spools are in a shelf above and this guide helps keeping the ptfe tube from moving around or go anywhere.

The inner diameter is 5mm. It is not a snug fit.  It is just a guide to prevent the tube from moving around. This will support 5 tubes.

Printing:

• Filament: PLA
• Infill: 15-20%
• No support required

UPDATE - 2024-12-14

Added a short version for a smaller footprint and make cables tighter. (TubeGuidex5 Short.stl)