New Wrist Trainer Ball Auto-Start Gyroscopic Forearm Exerciser Gyro Ball for Str

New Wrist Trainer Ball Auto-Start Gyroscopic Forearm Exerciser Gyro Ball for Strengthen Arms, Fingers, Bones and Muscles The product includes: JIN BD wrist ball Black without LED lights, brand card, ball bag, safety rope, instruction manual, gift box Automatic start: The upgraded version uses a built-in pre-tensioner to start, and no starting rope is required. Press the inner ball with your thumb and move your thumb in the direction of the arrow to start the internal spring. The working principle is simple and environmentally friendly. By rotating the wrist, the ball core rotates at high speed, generating centrifugal force, so that the wrist feels a certain resistance. Suitable for assisting: Long-term use of computers or mobile phones, carpal tunnel syndrome, repetitive stress injuries, etc. are more common. By continuously and indirectly strengthening the muscles and flexibility of the forearm and wrist joints, it can significantly improve muscle strength, flexibility, and promote b