This part angles pieces at 45 degrees from the grid. Use 2 at either end of a 7-block Rokenbok beam to diagonally brace inside a 7 x 7 block opening. Order this part on Shapeways: http://shpws.me/sCLG The files with the "Rep2" suffix are optimized for the MakerBot Replicator 2 to print at standard (0.2mm layer height) resolution with built-in support (no need to add supports in MakerWare). These designs are owned by Rokenbok Education (http://www.rokenbok.com) and published under license by kid*spark (http://www.kid-spark.org), a nonprofit corporation, for nonprofit and educational uses. Drawings of these designs are licensed under Creative Commons Attribution-NonCommercial-ShareAlike (BY-NC-SA) 3.0: http://creativecommons.org/licenses/by-nc-sa/3.0/ The drawings may be freely downloaded, modified, and used, providing that attribution is given to Rokenbok Education and the drawings are for non-commercial purposes. Any modified drawings are licensed under the same terms. The drawings are intended for educational and hobby uses only; 3D prints of these designs should not be considered toys or for use by children without adult supervision. The drawings are not guaranteed to print perfectly.