The X-One ball is a pressure competition ball that is a lively, fast, high-performance ball with good longevity. It is equipped with X D-Core technology that reduces the deformation of the ball during play by 20%. This innovation allows the core to retain its initial shape over a longer period of play. the same dynamic signature and therefore the same sensations. Play longer with the same gameplay. The choice of competitors. Used at the ATP tournaments, this ball is intended for high level players.