CLOGS
thingiverse
This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/1oHxY17t57f Just a modern version of a toy we had when I was young. Pull some rope through the holes and tie to make a loop. Kids stand on them and hold the rope while walking around. I made the first ones with 3x bottom, top and side layers and I could put my whole weight (>100Kg) on one with no problems.
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