Specification:Material: Imported Natural Rubber、 Tennis production special sythetic fiber. Bounce Height: 130-145 cm (Free falling from 2.54 m Height) Deformation: 0.23 - 0.26 IN. Recover: 0.315 - 0.36 IN Diameter: 63.5-66.7 mm Weight: 54.7 - 57.5 g   Feature: 1. Made of High quality natural rubber and Synthetic Wool. 2. Low Inner Tube Air Pressure、 Suitable for Children and Women\/Men Learning the tennis ball playing. 3. It can also be a pet training ball for your dog.   Package Included: 1*Tennis ball