Gooey, yucky, slimy stuff that can stick to many different things, at least for a while. Glow powder is added, but usually settles to the bottom of the plastic container. This is fixed easily by rolling and agitating the putty for a minute or two in your hands. Comes in four different colors of putty. They all glow green. Glows for 30 minutes to 1 hour in the dark after exposure to sunlight, houselight or black (ultraviolet) light.
