Chalk Brights Liquid Chalk Markers are great on all nonporous surfaces: whiteboards, blackboards, glass, glazed ceramics, plastics as well as Teacher Created Resources' Clingy Thingies® and Better than Paper® products. Versatile tips make it easy to produce narrow and precise lines or thick and bold lines as needed. Featuring opaque pigmentation and a range of bold, vivid colors, their water-based, non-toxic, wet erase ink removes easily with a damp cloth or sponge.