These gravity feed markers are filled with fast-drying oil based ink that is UV and water resistant. Magic Ink was developed in Japan and has been sold since 1953. Features a metal body and a fine 1mm to 1.5mm bullet tip. Works well on a variety of surfaces including: glass, paper, metal, plastic, leather, wood, ceramic and even ice! We Highly recommend you use these on stickers. For professional use. Keep out of reach from children.