Mini Hoberman Ball that expands from 5.5" to 12" in diameter with a magical motion that amazes everyone. Excellent for teaching breath control, "showing" how much or how little with an object. Our therapists love this ball for its versatility. Push any hub and watch it contract! Hoberman is known for thoughtful, innovative, educational and fun toys and the Hoberman sphere meets all these criteria and more. Great for helping children with special needs visually understand deep breathing and expanding their chest cavity for relaxation. Used in special needs yoga classes, as a reinforcer for ABA programs and more. Comes fully assembled, with a selection of game ideas. Instructions.