7 dry-erase markers for our silicone coloring mats. They can also be used on whiteboard by mom & dad ! Specifications ASTM D-4236 certified. Non-toxic for kids. Age 3+. Use & Care These markers are manufactured for our coloring silicone mats and are designed to be removable off non-porous surfaces. We cannot guarantee the complete removal of ink stains on materials other than our mats, particularly surfaces that are highly absorbent in nature. This is why we recommend also to cover and protect your work surfaces, as well as have some adult supervision especially with the little ones.