These pens will wipe off smooth surfaces and are only permanent on porous surfaces. Perfect For Rock Painting !Transform your house and possessions thanks to the multi-surface Giotto Decor Materials art markers.  ideal for decorating card, wood, glass, plastic, stones, clay or metal. Decor Materials markers can be used freehand to decorate glass and mirrors, and can be wiped off any smooth surface with a damp cloth .Available in 6 water-based non-toxic colours, safe and light-resistant with perfect coverage even on dark or coloured backgrounds, they come with a super-durable fixed tip and ventilated safety capAll colours are easy to wash off your hands, but they may stain clothing. The colours can all be superimposed, and can be applied to dark or pre-coloured backgrounds. Perfect for small jobs, and even for preschoolers. Age 3+