The DFX Sports Blue PowerBall offers everything you need to increase your range of motion and condition your arm, elbow, and shoulder muscles. The PowerBall incorporates an onboard generator and balanced rotor. By activating the gyro, a dynamism (motion) is created, which will activate six blue LED lights that are located in the interior of the gyro. The faster the unit runs, the brighter the lights will radiate until the whole hand is engulfed in a bright glow. The PowerBall generates 40 pounds of torque and speeds of up to 18,000 rpm, making it an ideal tool for physical therapists, trainers, and athletes who want to improve muscle condition and/or rehabilitate nagging upper body injuries. The PowerDock docking station activates your PowerBall gyro and serves as a modern-looking base to rest your gyro while not in use. The docking station requires two AA batteries (not included). Training CD is included.