Baoding balls are metal balls that are small enough to hold in one hand. They are also known as Chinese health balls, Chinese meditation balls, and Chinese medicine balls. They are used by rotating 2 or more balls repeatedly. They should touch each other. This set of baoding balls was handcrafted by Chinese cloisonné enameling techniques. The balls chime when rolled in your hand. The Yin and Yang decorations on the baoding balls are two symbols that represent opposing forces. Yin represents the passive, dark, and negative forces, while the Yang is the opposite. It represents the positive, light, and energetic forces. While they oppose each other, their characteristics are complimentary aspects of each other because without Yin, there would be no Yang. They are said to relive stress, focus the mind, and build dexterity and strength in the arms and hands. Comes in a red hinged box covered in red Chinese print material. The box shows a little wear, but not much.