This model is intended for use as an addition to the John Lewis Marble Run. I've printed it cleanly in Prusament PLA on an MK4S. It fits snuggly on both ends and maintains the correct height. In the photos, the green and blue tubes are the injection moulded pieces from the commercial set. The pink tube is this model printed in Prusament PLA.
It was modeled with Onshape.
Marble_Run_Tube_Segment_5.stl | 136.0KB |