We chose to mimic the rhombic grid of the Äppler glass - also called "Geripptes". The grid dates back to the days when people still ate food with their hands. Glasses without grids would've slipped out of the greasy hands. Our notebook is as handy as these glasses. Transparent UV coating was so thickly applied that you can actually feel the rhombic grid. The red rubber band and the red edge of the book quote the red color of Frankfurt's municipal coat.