Achieve controlled, consistent, smooth fluid lines for drawing, writing, illustration, and crafting with this Studio Series Micro-Line Pen Set! Set includes 6 different pens with black pigment ink in a transparent reusable storage case. 6 fine-line pen options. Sizes: 005, 01, 02, 03, 04, 05. Archival-quality black pigment ink. Waterproof. Fade-proof. No bleed-through.