This is a sign for use on an institutional Smartboard to notify faculty and students that the white ceramic-on-steel board is not to be used with whiteboard markers.Printed using 2 shells and 5% infill, PLA @ 170/60, travel rate 35mm on a MakerBot Replicator 1.Printed at 0.5 scale to fit three 5/16" rare earth magnets (Harbor Freight #67488) for a small board and full size for a larger board. Full size uses two each of the same magnet per hole on the back. Fixed magnets in place using superglue then backed the whole surface with self-adhesive craft felt to prevent scratches to the board's surface.