Combines mathematics, geometry and aesthetics into a magical motion of surprising simplicity, beauty and fun. Its system of polymer links expand and contract almost effortlessly, changing in volume 30 times. A sturdy toy, an object of art, a tool for teaching mathematics and science - the Hoberman Sphere's universal appeal and versatility have led its owners to discover uses even its inventor never dreamed of. Children love to wear it on their heads, or climb inside. Grown-ups have proved themselves no less inventive: jugglers juggle with them. Drill teams march with them. Magicians make magic with them. Teachers teach geometry with them. Motivational speakers use them as metaphors for unity, teamwork and expanding potential. Ages 4 and up. Expands from 9.5" to 30".