<https://community.ultimaker.com/topic/19249-how-to-tell-when-the-ptfe-coupler-is-bad/#comment-186740>
<http://schema.org/text>
"Do you have a picture of that cavity by accident? That would be very interesting to see. "
<https://community.ultimaker.com/topic/19249-how-to-tell-when-the-ptfe-coupler-is-bad/>