Adapter stud từ Duplo sang Kullerbü

With this adapter you can build towers with Duplo and switch over to the Kulerbü stud format. That way you can go as high as the number of Duplo bricks you have. Both the fit to the Duplo bricks as the fit to the Kullerbü units is snug. Print it up-side-down, that way you can print it without support.