High quality clear ball just like a gimnik ball. It is often used in therapy as instructors can see the movement of students and the the can observe the patients movements, and they are also pretty good. Comes with a W action pump that allows air to enter even if you push it or pull. Important: The transparency may differ from lot to lot. Also, since it is transparent, oil stains may be visible and air bubbles when molding inside the molding, but this is not a defective product.