POSCA Acrylic Paint Marker Set 16 - Non-toxic, water-based POSCA markers can be used on almost any surface so you can express your creativity freely. The alcohol- and solvent-free opaque paint covers well, is blendable, dries quickly and can be overlaid when dry. The pen has a valve mechanism for a tight paint seal and a ball inside the barrel that mixes the paint, allowing for even paint consistency, texture and continued optimal results.