This is the side (sort of) round thing on the sides of Cozmo's head. We wanted to be able to easily differentiate one Cozmo from the other, & my daughter is a fan of Disney's Descendant's movies. Hence the names on the other 2 versions.
Sorry there isn't a picture, but sense my printer has a .4mm nozzle I couldn't print with enough strength for it to work properly. You can try printing it if your printer also has a 0.4 nozzle, the clips that hold it on just might break off if you go to take the piece back out of Cozmo's head. I never bothered to try it, but you may also have better success if you position the piece at about a 45 degree angle.
Also, if you don't have a 3D printer let me know & I might be able to print them and mail them to you for a small fee.