Category: The tennis training balls are suitable for both adults and children for training purposes<br> Material: Made from rubber and felt materials, these tennis balls are designed to withstand heavy use<br> Size: Each ball has an approximate diameter of 6.4 cm/2.52 inch, making it the proper size for training sessions.<br> Elasticity: With an elasticity range of 1.1 from to 1.15 m, these tennis balls provide a good flexibility that enhances your training experience<br> Packaging & Storage: The set includes 20 tennis balls packed in a drawstring bag for easy storage and transportation<br> Specification:<br> Material: Rubber Felt<br> Size Chart:<br> Diameter: 6.4 cm/2.52 inch<br> Package Includes:<br> 20 Tennis Balls<br> Note:<br> Please allow slightly errors 1-2cm differences due to manual measurement.