Buzzing Bee Thinking Putty® starts off black but warms to yellow as you play with it. It springs right back to black as it cools, just like the colors of the stripes on a buzzing bee! Thinking Putty® helps build hand and finger strength through a fabulous tactile play experience with unique, unexpected properties and provides relaxing, yet stimulating interaction for anyone with sensory integration issues. Thinking Putty® is non-toxic, won't dry out, and won't leave a sticky or slippery residue on your fingers, so it's great for stretching, molding, bouncing, tearing, popping and playing by kids and adults alike.