Gently colored line marker that makes letters easy to read and stand out" Mildliner is a line marker with a gentle color tone. Compared to regular highlighter pens, the Mildliner's low fluorescence and non-intrusive nature make it easy to read and reread text in notebooks and organizers. The water-based pigment ink does not migrate to the back of the notebook and comes in a wide variety of 35 colors, allowing you to create your own unique notebook. Line thickness: Thick 4mm / Fine 1.0-1.4mm. Ink: Water-based pigment.