Included in the package are two ruling pens. These pens are made of plastic and stainless steel, and are colored green. They have a length of 12.5cm and weigh 7.2g. To cover a certain line or space, simply dip the pens in masking fluid and move along. The thickness can be adjusted using a screw. These pens are suitable for drawing lines and borders in ink, watercolor, and gouache.