This unit comes with a FREE Smart Charger. A truly portable ball machine that will fit in the trunk of your car. Features wheel drive, 150 ball capacity, adjustable ball speed and built-in oscillator. Model 3 has a remote control. Tennis Tutor is truly portable, measuring only 12 inches tall when the ball hopper is folded down for transport. And with the towing handle extended, it tows just like luggage. When you get to the court, the ball hopper opens in seconds to hold 150 balls, which is more than two standard pick-up baskets full of balls. Tennis Tutor comes standard with a built-in heavy duty rechargeable battery that can deliver up to six hours of playing time, so there's little need for extra batteries. But if you do want more battery life there is an optional External Battery Pack. Tennis Tutor has a built-in battery charge indicator, and it even politely beeps when there is only one-half hour of battery charge left. And of course, Tennis Tutor comes complete with a plug-in charging unit that fully charges the battery overnight. WARRANTY: 3 year limited warranty on parts and labor (NOT including battery) Features: Ball capacity: 150 balls Trajectories: groundstroke to lob Ball ejection speed: 10-85 MPH Ball feed rate: 1-1/2 to 10 seconds Oscillator: built-in Playing time with heavy duty battery: 4 to 6 hours typical Anti-jam ball feeding mechanism 10-second start-up time delay Adds topspin and underspin capability Sports Tutor 3174-1