Sports Tutor Tennis Cube ball machine very simply does what any ball is supposed to do; throw tennis balls so that strokes can be practiced. Simply turn the machine on, set the ball speed, adjust the elevation if necessary and you are ready to start practicing. The Tennis Cube can be adjusted for the ball interval from every two to ten seconds, and anywhere in between to ensure you can practice at your own pace. Tennis Cube holds a standard pick-up basket of 70 balls and even politely waits ten seconds before the machine begins throwing balls, after the Tennis Cube is powered on. A smart battery charged is included that recharges the Tennis Cube overnight, and which can be left plugged-in continuously without overcharging the battery. The optional horizontal oscillator .
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