The 12 pieces are all the possible arrangements you can make by placing 5 squares next to each other.
The goal of the puzzle is to fit all 12 pieces perfectly in each one of the 4 different sized frames.
Good luck!
You shall not share, sub-license, sell, rent, host, transfer, or distribute in any way the digital or 3D printed versions of this object, nor any other derivative work of this object in its digital or physical format (including - but not limited to - remixes of this object, and hosting on other digital platforms). The objects may not be used without permission in any way whatsoever in which you charge money, or collect fees.