This is the gyroscopic trainer that burns calories and strengthens the upper body using centrifugal force. At only 3" deep when its handles are removed for packing into a suitcase, the portable gym employs only a 1-lb. weight to generate ample resistance for burning calories. Simply grip the handles and swing the strengthener in a circular motion, as if turning a crank with both hands. The motion causes its internal swing arm to spin, with smaller circles creating a faster revolution that increases the intensity of the cardiovascular and muscle workout. Raising or lowering the strengthener and bending or straightening the elbows targets different muscles in the torso and limbs, while the integrated tachometer calculates the RPM and workout duration. Results are displayed on the LCD screen, which requires one 9-volt battery. 11" H x 10" W x 5" D. (3 lbs.)