High Performance: can effective separate and train fingers; increase finger flexibility; prevent finger joint deformation and muscle atrophy, Effectively relieve finger cramps and numbness, infrared massage, promote blood circulation. Charging Device: usb interface, with a 1200mAh battery, which can be used for about 120 minutes and fully charged for about 120 minutes. Comfortable To Wear: Wrist massage ball is suitable for fingers without independent grasping ability. making it more comfortable to wear.effectively relieve finger spasm and numbness, and prevents finger cramps or atrophy. Wide Range of Applications: It is suitable for suffer finger flexion convulsion, cerebral palsy, finger dysfunction caused by cerebral infarction sequelae, hand muscle atrophy and other reasons. One Size Fit All:Fits both right and left hands, This ball fits comfortably in your hand to help reduce hand contractions and spasms.