A medical device includes an interface unit body, which is configured to hold a portion of a flexible infusion tube. A hinge insert is fixed to the interface unit body and is configured to engage a hinge receptacle, which defines a hinge axis, on an infusion pump. A catch insert is fixed to the interface unit body and is configured to lock onto a catch receptacle on the infusion pump upon rotation of the mechanical interface unit about the hinge axis while the hinge insert engages the hinge receptacle, so as to bring the tube into engagement with a peristaltic mechanism of the infusion pump in order to enable the peristaltic mechanism to propel a fluid through the tube.
