The Ion Glow-in-the-Dark Putty from Crazy Aaron's Puttyworld is a great stress-relieving toy children and adults alike! Designed for ages 8 years and older, this set comes with a tin filled with 1/5lb of Thinking Putty, in a bright turquoise glow.This putty is milky white in the daylight but glows when the lights go down . . . after exposure to light, the colors can glow for hours. This putty is fun to play with, but also provides stress-relieving qualities while you play---try writing messages or drawing pictures on the putty and watch them glow.