These products don’t contain wool, leather, or animal-based byproducts according to their manufacturers and an independent lab has verified that the featured balls don’t contain wool. That said, there is no sufficient replacement for vegan certification and the thorough auditing process it entails. That’s why we’re striving to manufacture the world’s first certified-vegan tennis balls and asking tennis ball companies to help make tennis vegan by producing certified-vegan tennis balls themselves. In the meantime, we hope you find this catalog of vegan tennis gear helpful. If you’re interested, you can read more about our verification process here.