This is a keychain based on the logo of the international student association Best. You have more info at: http://bestmadrid.org/web/I made this keychain using the logo design: http://www.thingiverse.com/thing:853760 If you want to print the keychain you'll only need the .stl file. In case you wish to make some changes you'll need the two .scad files and also the .dxf file. Remember to put all of these files in the same folder.