Kids will love playing "Mad Scientist" with this Glow in the Dark Lab Putty™! Mold it, knead it, bounce it, twist it, stretch it, snap it, and melt it. To activate glow, expose putty to bright light. Part toy, part stress reliever, and entirely addictive! The putty never dries out, and leaves no residue, so the fun never ends! Recommended for ages 4 and up.