The CanDo Wrist/Forearm Exerciser allows the practice of repetitive functional movement to rehabilitate the wrists and forearms. Use it to practice exercises such as flexion, extension, pronation, supination, as well as ulnar and radial deviation in the hand and wrist. It is perfect for patients just beginning rehabilitation because of how little physical strength is needed to be used. Use the semi-spheres and handles together or use the semi-sphere individually. This set comes with 1 extra large - yellow semi-sphere and handle.