Copper PenTouch opaque paint flows from the chamber directly to the top of the marker. A quick shake before writing gets the paint flowing and mixes the color. This marker writes on glass, wood, porcelain, plastic, paper, metal, but shows best on non-absorbent surfaces like coated paper. Our low odor, xylene free, archival quality ink is chemically stable, waterproof, and fade resident. Although permanent on most surfaces, it is not permanent on glass or ceramics. Also, it is not recommended for use on fabrics intended to be washed.