So Fetch! Tennis Ball Pack of 7 - IvoryGame. Set. Fetch. Weve taken the classic tennis ball and given it a chic new spin. Designed with a natural rubber core and durable, pet safe felt, these balls are built for endless rallies of fetch. Finished in elevated colors, they bring court side style to every play session because fetch should feel like a win for both of you. Product Details: Natural rubber core Pet safe felt Durable + non toxic Elevated colorways Standard size: 2. 5 in Caution: