These are 3D *.STL files to print out the internal gridwork as seen in the video for the book nook. The only other file you need is a file for the astronaut as found on Thingiverse The Death Astronaut By Max Guenther. Go there to get it since it is not my file. After printing the grid, just follow my YouTube channel video for how to put it together. As always, I can answer any questions you might have!https://www.youtube.com/watch?v=lgKC3op7hdA&t=217sHappy Modeling.