A rainbow of primary colors effortlessly changes volume up to 30 times& #33; Colorful linking rings provide hours of fun& #33; Welcome to the wacky world of Chuck Hoberman& #33; The Hoberman Sphere expands and contracts with a magical motion so fluid and simple that kids can't help but play with it for hours. A master of illusion the Hoberman Sphere can be thrown bounced kicked spun rolled or suspended from the ceiling. The polymer links allow the sphere to change in volume 30 times and the rainbow of primary colors swirl as it is tossed and contorted. Includes an educational booklet about the Sphere a "21 Cool Things To Do" activity sheet a pulley hardware and instructions for hanging as a cool kinetic energy mobile. Collect them all& #33; For ages 4+.