Yoga Ball Made From Cork. Cork is a Natural Material Derived From the Bark of Cork Oak Trees. It is Often Used in Various Products Due to Its Unique Properties, Such as Being Lightweight, Durable, More Sustainable & Providing a Non-Slip Surface. It has a Natural Texture That Provides Excellent Grip, Even When the Ball Become Slightly Moist From Sweat During Yoga Practice. Diameter: 6.5 Cm. the Pouch is Made of Recycled Polyester. Minimum Quantities Apply.