Our Clip-On Ball Allows for Convenient, Easy Access to Your Pets Fetch Ball(S). Attach One Or More to Your Pet's Leash, Simply by Pinching the Clip-On Ball, And Inserting It onto A Taut Portion of The Leash. The Twin Teeth Supply the Clamping Force to Secure the Ball to A Majority of Dog Leashes on The Market, And Is Designed for Both Large and Small Breeds.