Set of 2 yoga balls 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 and 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.