I purchased the Large Aqua Kong and was a little hesitant inasmuch as my ball-driven German Shepherd over the past five years has destroyed all types of tennis balls in a matter of minutes. I needed something that floats, as she swims non-stop and has jaws of steel. The Aqua Kong is BEYOND FABULOUS!!! My dog cannot destroy it (and she has tried). I have even run over it in the car by accident and it doesn't destroy it. I now save $8.88 for a dozen tennis balls over a three week period. It is priced great and I now wish I had ordered two at the same time to save on shipping costs. I just didn't know if it would work out as I have tried EVERYTHING, even the tough tennis balls. I thoroughly recommend the Aqua Kong for any water (and land sport)for dogs.