Rotring Rapidograph Ink Cartridges - Black (Box of 3) - High density of pigment particles for opacity and lightfastness - Designed for line sharpness and adhesiveness - Fast drying and smudge proof - Ink is waterproof for long-lasting results - Can be used on many surfaces such as line-board, vellum drawing paper or tracing paper - Not suitable for tattoo usage What's in the box Rapidograph Cartridges