Pigma pens are versatile, fine lined, archival, permanent writing tools. To insure complete consistency of color and shading, the color in the ink is derived from a single pigment (unlike dye-based inks). Pigma ink is waterproof, quick drying, and fadeproof against sunlight or UV light. These pens will write on any porous surface. Pigma Pens are available individually in black, in a set of all 6 different point sizes in black or in a set of Black Red, Blue, Green, Brown and Violet.