I did see another one, though. And I thought "Maybe. Maybe this is the one."
Bigger than a regular tennis ball, the "Mashers" tennis ball was far harder to squeeze. It seems that it's solid...rubber or whatever. Not hollow, like a regular tennis ball.
Elka was, as always, a willing and vigorous participant. But, what's that?
Solid or not, the freaking thing is still covered with splittable, peelable, fuzz. And guess what the main problem I had with "sport" tennis balls in the first place? Fuzz. Fuzz that wears down doggie teeth. Fuzz that Elka, dear Elka, peels off of the tennis ball and chews up and strews on the floor and (I daresay) swallows if we're not wary.
You can see the starting to be deep teethmarks in the ball itself, that Elka so kindly exposed for your viewing pleasure. Great idea. I guess. But another fail.