Posca Paint Pens are opaque, vivid, non-toxic paint pens that can write on almost any surface. When used on non-porous surfaces like glass or chalkboards it can be erased, but on porous surfaces like paper, it will be permanent. These pens are used often to decorate surfboards, skateboards and to write on windows. It shows up well on light or dark surfaces. Comes in multiple tips size.