Diameter: 16 cm Weight: 310 ? 330 g Technical features: separate internal air chamber; high grip; made of soft pvc and bounces with small exerted force; excellent shape that keeps it free from vibrations when thrown and rolled; latex free. Recommendations for use: The ball is intended to be used only and exclusively for training and rhythmic gymnastics competitions on FIG approved carpet; Avoid use on rubber or linoleum surfaces in order not to compromise in any way the technical and aesthetic characteristics; It is advisable to store it in your Pastorelli ball holder immediately after use; The company is not responsible for stains or dirt due to incorrect use or maintenance of the ball even if kept inside Pastorelli ball holder; In case of travel, total deflation is not recommended; in case of re-inflation, lubricate the needle to prevent the displacement of the valve. If these conditions cannot be met, Pastorelli Sport recommends the purchase of the New Generation ball. The ball construction involves the joining of the two hemispheres, which then may present a small line. This does not represent a factory defect.