Just another lego-duplo compatible brick, or better said a set of two bricks for coupling two duplo car bases. The 2x2 module I used for them is also included. Test with real duplo cars: https://youtu.be/OeL-DKnaXXk

The geometry and the size are my rough estimation! The tolerance between the bricks is 0.15mm on each side, so 0.3mm between two bricks. The tolerance between the stud and the brick-bottom is 0.08mm on each side/contact. If your printer is quite worse/better calibrated than mine, the bricks might not fit (for example if yours is over extruding a lot).

The blue ones are the first version, which had a 0.4mm smaller height. The red ones correspond to the files with V2 in the name, these have a duplo-like or duplo-compatible height.

My print settings (PLA) - 0.2mm layer height - no support - 4 perimeter walls - 25% infill

Happy printing!

PS: if you're interested in other 3d printed toys (fully 3d printed actually), check out my other fully printable models