Quality Material: These Tennis Balls are constructed from rubber and tennis felt, featuring a soft inner core and a comfortable grip. They offer excellent elasticity and durability, making them suitable for long-term repeated use. Features: These Training Tennis Balls have a diameter of approximately 6.4cm/2.52inch, ensuring resistance to hard hits and the ability to retain their shape even after frequent use. Resilience Effect: They include a resilience function that adds an extra challenge to your training sessions and enhances your reaction speed. The tennis ball is designed for long-term use, even with regular training. Wide Application: These Training Balls are ideal for various scenarios such as tennis sports, outdoor training exercises, tennis matches, competitions, etc. They can also serve as interactive toy balls for playing with dogs. Great Gift: This set of Tennis Ball Toys presents a wonderful gift for family members or friends who enjoy playing tennis, as these tennis balls will improve their skills and add enjoyment to the game. Specification: Material: Rubber, Tennis Felt Size Chart: Diameter: 6.4cm/2.52inch Package Includes: 6 Tennis Balls Note: Please allow slight variations of 1-2cm due to manual measurement.