I wanted to use my printer the day I set it up, and the printer did NOT ship with a filament runout sensor mount. Found one on printables, but it needed an added pneumatic adapter which I didn't have - so I remodeled it to just hold the PTFE tube directly. Mounts right to the top of the printer in the original hole for the PTFE tube guide screw.
Note- When you use this filament sensor mount, you do not use the gold screw with the round hole at the end of it. Instead, there is a screw hole in the body of the mount meant for a flush M5 angle head screw. (Might be M4, I forget)
The author remixed this model.
This version does not require the added Pneumatic coupling part.