ProKennex Ki Pro 7G Classic (315) Kinetic Classic. A true baseliner's frame with lots of pop, due to racquet stiffness and 1/2" longer frame than standard. Adding a second energy soucre makes the difference. All racquets have a single energy source, the frame. ProKennex has developed a proven second energy source through its patented Kinetic System. The term "Kinetic Explosion," used to define the incomparable energy release that takes place in the Kinetic Series racquets, shot after shot, accurately describes the impact the technology is having on consumers. ProKennex feels a deep commitment to helping players with their game while at the same time increasing the longevity of their playing ability.With 56% incident of tennis elbow among tennis players, the market for this technology is in demand. Technology Kinetic Technology: It’s all about kinetic energy. As you swing the Kinetic racquet forward, tiny elements of kinetic mass, housed in dozens of chambers around the racquet head, are storing energy. When the ball hits the strings, the strings flex and the ball compresses. The ball speed drops to zero. The ball and strings are now loaded with energy. Finally, the racquet frame flexes backward as your swing continues. Going with the flow, the ball assumes the racquet’s forward speed. Forces are now in place to set off a scientifically calculated Kinetic reaction. The ball and strings now start releasing their stored energy causing the ball to go faster than the racquet. At this momegy release from the ball and strings triggers the kinetic mass. It explodes forward in all 100 chambers. This activated mass joins with the mass of the racquet to increase the area of efficiency of the hitting surface and magnify the possils after you’ve hit the ball? That ripple of vibration? The Kinetic System virtually eliminates this sensation. Once the ball leaves the strings, the tiny elements of kinetic mass actively damp this now-useless energy. This vibration is absorbed as it attempts to work its way through layers of active kinetic mass. The vibration energy is efficiently quieted. You’ll notice a huge reduction in wear and tear on your body and an increase in the efficiency as a player.