[Updated] Duplo compatible building block 2x4 - no support required

This is a Lego Duplo compatible 2x4 Block, which can be printed without support. Thanks to your comments I tried to improve the brick to better integrate with original Duplo Bricks.
I also tried smoothing the edges, but in case you still think it is too sharp, please use light sandpaper to improve the edges.

For optimal print use small layer heights and 0.4mm nozzle. I used PETG for the test prints, but PLA will be better suited for children. Make sure your printer is properly calibrated (esteps) for optimal fitment. It can be a bit tight to insert the printed bricks in the bottom of the original bricks, but not too tight. It is just holding pretty well with the current model.

I'll try to add some additional bricks in the future, to give a bit more variety.
Let me know how you like the new iteration!