The PSE, Pro Version of the Ki 15 is for high level players. The Kinetic Ionic Technology or "AKS" Advanced Kinetic System is a performance enhancing "engine". Much like adding a new engine that delivers more horsepower and better fuel economy to an existing automobile. This new engine brings significant and noticeable performance improvements to an already existing product. The PSE model is weighted and balanced for advanced players.
Pro Kennex designed this racquet for players who use a medium speed swing style. They would benefit most from the moderate to high level of power within the frame.