Glow in the dark paint pens are great for paper, wood, fabric, plaster, canvas and more. The glow-in-the-dark pigments contain phosphors that absorb UV light photons and hang on to them, slowly emitting new photons with much lower energy giving a soft glow you can see in the dark. Clean up with soap and water. Store with cap tightly secured in a cool, dry place. Use the magic black light flashlight sold separately for full effect. Recommended for ages 3 and up.