This Slazenger has created the world's ultimate performance tennis ball with several key technologies. The premium woven cloth is specifically designed for championship play, using the finest wool to achieve a tighter weave. These fine qualities result in increased durability and also responsiveness. Hydro Guard also uses patented technology which creates a cloth repellent to 70% more water than any other standard ball. It has been modified at a molecular level to offer more consistent performance characteristics that players of all levels can rely on.