These superfine technical illustration pens feature waterproof, archival india ink that will not smear, feather, or bleed on most papers. When used with a light hand, Microns always provide smooth, consistent, and skip-free lines. Perfect for illustration, mix media, journaling, drafting, or accounting. Individual pens come in black, green, blue, and red, in a variety of sizes: 005 (.20mm), 01 (.25mm), 02 (.30mm), 03 (.35mm), 05 (.45mm), 08 (.50mm)