The dual brush tips allow you easily lay down thick, thin, or varied lines in one stroke and work well for coloring books, signing, design, art projects,s and hand lettering; a 0.4 mm fine point tip is great for outlining, detail, and drawing. These double-end markers are a must for your next masterpiece. The dual brush pens have 36 vibrant colors and the colour-coded pen holder allows you to easily choose the right color every time. The vibrant rich ink is water-based allowing creativity by adding a bit of water for fading of colours and a water painting result.