NSD Powerball Gyroscopic Dumbbell
Used by NASA astronauts to maintain their upper body conditioning in space, this is the gyroscopic dumbbell that strengthens and rehabilitates muscles in the hands, wrists, arms, and shoulders.
Holding the tennis ball-sized device and rotating your wrist causes the internal gyroscope to spin up to 13,000 rpm and provide up to 38 lbs. of torque resistance to strengthen the wrists, biceps, triceps, and deltoids.
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