Bought some plastic boxes from OBI and Tesco, but my son somehow managed to break those molded rollers which came with the boxes, so I've decided to take my learning and design a matching roller. It fits for both. Tried to follow parametric design, but since I'm not an expert there might be better solutions, but here's mine.

An example box: https://www.obi.hu/tarolo-dobozok/obi-univerzalis-doboz-santos-oversize-41-cm-x-77-5-cm-x-58-cm-140-l-atlatszo/p/3234432

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