Filler: 3-D PP cotton; rubber particles; rubber thread. Reject the use of wet filler, to ensure a dry and not damp.
Sphere filling is using parcel special filling process, not a mechanical fill . Ensure the stability of the sphere center of gravity, during the use of process without deviation, beneficial to the athletes play .
Repeated research trials, according to different proportion, to optimize the ratio of filler to ensure that the sphere is round and non -deformation