The Uni Pin Marking Pen writes with rich, black oil-based ink that holds up on paper, plastic, glass, and fabric, making it one of the more versatile pens in a planning kit. It works well for labeling dividers, writing on washi tape, or marking transparent sticky notes and page flags where a water-based ink would smear or bead up.A fine felt tip produces a bold, solid line built for technical drawing and detail work, and the pen writes for roughly 2000 meters before running dry. The gray body has a snap-on cap that can be posted for a longer reach while writing.Features Black oil-based ink 0.49 mm fine felt tip Writes on paper, plastic, glass, and fabric Acid-free, dye-based ink Snap-on cap that can be posted Not intended for use on most papers, as ink will bleed through Product listing is for one Uni Pin Marking Pen only.