Meditation balls - also known as Chinese medicine balls, Baoding balls, relaxation balls & Zen meditation balls - are two little balls that can be held in one hand. As you roll them in the palm of your hand, the relative positions of both balls is constantly switching. Initially, the balls maintain contact even as they are rotated. With practice, your hands eventually learn to manipulate these balls without having them touch each other. Meditation balls purportedly improve brain function while they exercise your hand muscles. Some people believe that meditation balls help reduce stress, in which case they may be called worry balls. Benefits: Relaxed joints & muscles Stress & anxiety relief Improved memory Enhanced quality of sleep Material: Iron, Resin, Copper Dimension: Size: 4.7cm Diameter Weight : Approx. 235g Yin Yang Chinese Meditation Ball, Baoding Balls, Zen Stress Relieve Balls