The X-One tennis ball is the official ball of several ATP 250/500 tournaments such as Marseille, Rotterdam and Gstaad. This is a top quality ball manufactured by Tecnifibre and another company. These balls were designed using the highest quality materials to create the ultimate tennis ball for competition play. The Technifibre X-One was the official ball of the Davis Cup Finals in 2017. The key characteristics of the ball are liveliness, speed and durability. Don’t let your game suffer from an inferior tennis ball, get the balls the pros choose with Tecnifibre X-One. The four ball can means less time chasing balls between points.