1. Standard Specifications for Beginner Use This tennis ball has a diameter of 63.5mm-66.7mm and a weight of about 54.7g-57.5g, complying with the standard size and weight requirements for beginner training. It is an ideal choice for physical education courses and novice entry-level practice. 2. Multi-Layer Material for Durability Adopting a three-layer structure design of rubber compound inner bladder + wear-resistant middle layer + chemical fiber outer layer, it is impact-resistant and wear-resistant, and not easy to deform or break after repeated hits. 3. Stable Elasticity with Excellent Rebound Effect The elasticity coefficient meets the standard. When dropped from a height of 2.54 meters, the rebound height on hard ground can reach 1.3 meters-1.4 meters, providing stable hitting feedback and enhancing the training experience. 4. Multi-Scene Application with High Practicality In addition to beginner tennis training, it can also be used as a pet interactive toy and a muscle massage ball, achieving multiple uses in one product to meet different needs. 5. Brand Quality Assurance Produced by Boka, a professional sporting goods brand, the material and craftsmanship are strictly controlled, providing cost-effective tennis balls for beginner users.