ZIG Fudebiyori Metallic pens are a water-based pigment with a semi flexible hard brush tip allowing you to easily control strokes and lettering. Effective on dark colored papers. Waterproof / Archival Quality / Flexible brush tip is effective for both details and larger spaces / Especially effective on dark colored papers. INK TYPE: Photo-Safe, Acid Free, Lightfast, Odourless, Xylene Free, waterbased pigment