Sakura's Pigma Micron Pen offers permanent, waterproof, pigmented ink in a fine-point drawing and writing pen. Artists, writers, and illustrators reach for Sakura Pigma Micron Pens to convey their personality, style, or ability, and to safeguard their work with the lasting quality of Pigma ink.Details: Includes assorted colors (light cool gray, cool gray and black) Tip sizes range from 0.25 mm to 0.6 mm 6 sets (10 pens per set) Waterproof Acid-free Archival ink