Inspired by nature's abundant colour spectrum, these Graf von Faber-Castell inks allow pen connoisseurs to express their moods and ideas in their own individual style and in a rich variety of colours. These international cartridges are suitable for any Graf von faber-Castell fountain pen but fit also a range of other fountain pens. They are available in a pack of 6 or in a beautiful refillable box of 20 cartridges.