This is for one size Medium ball. Remember, each ball is handmade, so there can be a slight variation in size within each size ball and color. Every ball is unique. Most recently, we "reinvented" the fetch toy. Our WUNDERball is 100% made by hand in North America and is much more than just a "ball." They Clean Teeth, Bounce Unpredictably, Float, Roll Farther and we GUARANTEE them to be INDESTRUCTIBLE. WUNDERballs are made from the excess material from our award-winning "no-pull" leashes - The WACKYwalk'r. Using our excess material keeps costs down but also helps us do our part in becoming a more eco-conscious, forward-thinking, sustainable company. Available in 4 sizes, they are safe for Pups and the Planet.