Just like its name implies, Liquid Glass Thinking Putty is unlike anything you've ever seen. This crystal-clear creation is so transparent that the tin often appears empty to the naked eye. Liquid Glass putty becomes cloudy with use and changes back to crystal clear. Liquid Glass is the only Thinking Putty collection that stands alone in putty properties. Liquid Glass will never have the elasticity that the other putties do; they simply don't have the composition. Liquid Glass stretches a bit before breaking and does not bounce. This Thinking Putty is meant to be enjoyed for its transparency. Thinking Putty helps build hand and finger strength through a fabulous tactile play experience with unique, unexpected properties and provides relaxing, yet stimulating interaction. Crazy Aaron's putty is non-toxic, won't dry out, and won't leave a sticky or slippery residue on your fingers.