POSCA opaque felt tip markers can write on a variety of surfaces including plastic, metal, wood, glass, plaster, canvas & more. Paint can be scraped off from nonporous surfaces like glass, but will adhere permanently to porous surfaces such as wood & paper. Water-based pigment ink is non-toxic, light-fast & waterproof. The ink won't bleed through paper (unlike alcohol-based markers) & is excellent for vibrant signs & craft work. Marker Ink Type: Permanent; Marker Tip Type: Bullet; Marker Tip Size (text): Medium; Marker Color(s): Assorted.