Olive Wrist BallWrist, Exercise Adult Adjustable Hand Forearm Strengthener Wrist Training Ball for FitnessFunctionThe forearm strengthener is great for wrist forearm training, building up wrist strength. A great gift for family and friends. Olive Wrist BallThe wrist ball is exercise the wrist, it can be adjusted at will. The faster the ball core rotates, the greater the power will be. Ergonomic Grip DesignThe Wrist Ball is ergonomic and easily used. comfortable grip. Automatically start the design, easy to use. High Quality MaterialWrist Gyro Ball is made