They have many benefits for the hands, wrists and arms being able to increase muscle strength and definition. Inside there is a finely engineered and precision crafted gyro with a rotor that spins rapidly once the device has been started either by a rip cord or electronic starter. When the gyro is spinning, a tipping action will cause it to precess and move in a circular motion to generate the force to continually increase the speed, which in turn acts with a greater resistive force against your body. The inside of the device is useful for increasing finger, hand, wrist and arm strength as well as increasing blood flow and restore the full range of movement in joints. The Powerball (or hand held gyroscope) is a truly dynamic object, there are no batteries and no electricity used, unless you have a model with a rpm counter. Using the theory above, you rotate the powerball with a circular wrist motion in either a clockwise or anticlockwise manner, it's works in both directions. Music, Picking, strumming, holding, twisting, see marked increases in wirst and finger strength - essential for all musicians For more reasons than one, the Powerball

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    More about this product Brand new and boxed Powerball 250Hz, Neon Green Regular, This is one of the .by Nsd Powerball.Powerball Gyroscope Neon Green Regular

    Image: Powerball Neon Green Regular
    Green.Red .Colors.Click to view colour.Image: Powerball Neon Green Regular Powerball Neon Green Regular.Blue