describe: Function The grip strengthening ball can promote the recovery of hand injuries and enhance the strength and flexibility of the hands and fingers. The perfectly designed four-finger grip strengthens the fitness ball, making it more secure. The size is suitable for most people, especially for athletes, musicians and physiotherapy. The easy-to-carry hand-held strengthening exercise ball can be taken out of your pocket or school bag whenever you need it, because it is exquisite and small. Production material The grip ball of the exerciser is made of high-quality Tdr material, which is not easy to deform, harmless to the body, and tactile massage. After-sales service It is our pleasure to serve you. If you have any questions, please feel free to email me. We provide 24 hours attentive service.