This Micron fine line pen set from Pigma is a must have in every artist's kit. With fine tips and high-grade ink, these pens are the perfect tools for watercolor artists and illustrators to enhance their work. Details:BlackSize 01 (0.25 mm)6 pensDoes not feather or smear when dryWill not bleed through most papersWaterproof, archival quality, permanent, fade- and chemical-resistant Pigma inkMeets ACMI non-toxicity standardsConforms to ASTM D-4236Not for use on fabrics that will be washedNot for use on skin