Ink properties: quick-drying, erasable with hard scrape and soluble in water. Conforms to ASTM D-4236 certificate, non-toxic and acid free. But don't swallow it and No food contact
Smooth Writing: Writes on nearly all smooth surfaces with your imagination and creation, allowing you to easily write on paper, stone, rubber, ceramics, wood, glass, plastic! Not suitable for porous and rough surfaces.