I have designed these for easy to click on and off, moreover it makes it easier to clean after use. All feet is stored separately and can easily fit into the Helinox chair zero storage bag together with the chair. It is also possible to make the diameter even bigger in the slicer if needed for another setting for example the beach or other.

The Helinox foot adapter is 50 mm in diameter and is designed as a shoe to go over the standard feet and will increase the footprint of the chairfeet so it does not sink in the ground.

These should fit Helinox Chair One, Chair Two, Chair Zero, Chair Zero L, Chair One Mini, Chair One L, Cot Extension Legs. And chairs with similar 45mm feet.

I have printed these in PETG with 4 walls. But I think that it will work fine in PLA too.  

Print without supports.