The end stick of the mop rod went to bruch, so I have a new end piece designed and printed out.

I measured the mop rod with a diameter of 26.6mm. As filament I used black PETG.
I imagine that PETG is a bit more flexible and holds better on the rod. With PLA it would have worked as well.

I printed the whole thing with a brim and 2 layers as wall thickness. 4 layers each (standard) for top and bottom and 15% infill (gyroid).