Spirograph Geometric Ruler and Drawing Toy. Can be used to make various patterns and designs Dimension: 20*10 cms Usage: Place the ruler on a sheet of plain paper. Place the small circle provided inside the ring. The point of a pen is placed in one of the holes of the circle. As the circle is moved, the pen traces out a curve. Pens of various colors can be used, to add texture and color to the design by switching colors in a set pattern or a random fashion, as seen in the image above. Each set contains 1 ruler with drawing tool and 3 circles to draw patterns