Get the Flash Video Player to see this video.
As you discuss optical illusions, you display two curved plastic strips with designs of cats printed on them.
To your spectators, it appears as though the strips stretch and shrink as you demonstrate a classic and well-known optical illusion.
At the climax, however, your spectators are taken completely aback as it is proven that both strips have actually changed their size for real!
Quality props and routine from Seo Magic.