Designed with the 8-12 year old in mind. Frame is extremely user friendly for youth league age boys and girls. Includes training CD and six 9 plastic balls and an extra trigger string. Place a ball on the launcher, load your hands back as you stride to landing on the firing cord. The ball appears in the hitting zone with you in the ideal position: hands back, foot down, hips leading to the ball. Feel and teach how to load/coil your body as you stride to hit and the effortless power that comes from torque. Promotes balanced stride and faster bat speeds. Spring loaded power source allows use of balls varying weights and sizes. Rigid construction.