Super5 Pens & Inks Germany G16554 Ink, 30ml, Gray Super 5 inks for fountain pens are 100% waterproof Painting sketches and drawings in watercolor with either your pen or a brush is now possible with fountain pen ink The ink is waterproof and lightfast just like the best watercolors, very unique from other ink Ideally suited for contour drawing which can be colored with watercolor or gouache. Popular with the Urban Sketching movement