Having some pairs of Croc in heavy rotation, it is common to break the heel strap connector.
So I tried most of the connectors already available, but found no one working to my expectation. Either you had to glue it or the clips were always snapping off already while assembling.
I also found that my different Croc come with different diameter in the heel strap. Most straps are made completely out of the soft material (8,4mm loophole) and others have a hard plastic loophole (8mm) where the clip cant be bent outwards while snapping it in place.

So here we go:
8,4mm for soft straps (for easier assembly you might also use the 8mm male)
8mm for hard plastic loopholes

FreeCAD file included if you want to further tune the geometry.

I was deliberately using my oldest printer (A8) with the poorest print quality to check the printed design and it still works.
I suggest to use PETG for the better flex, but PLA should work as well.

If you have any comments, just let me know.

Modified the female clips (now v3) for more stability while snapping in the male.

Anet

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