Four metal lettering rulers and a rotating lettering system device are included. The sizes are as follows: 50 cl, PEN 0.10, 60 cl, PEN 0.2, 100 cl, PEN 0.3, and 120 cl, PEN 0.4. Include Rulers for Lettering Individual/set & Isographs Inserting the Isograph by its very tip into one arm, you use the metal tip fitted on the other arm to follow the grooves on the rulers. It is possible to shorten or lengthen the distance between the two arms. This has an impact on how the letters are rendered. The letters are vertical in the smallest space and slanted in the larger space (see sample pictures of minimum and maximum angle). Other Brands with comparable systems included: Leroy Keuffel Esser K&E Lettering