My Jack Russell gets a crazed look on her face as soon as she hears the noise emitted by this toy.  Keeps her busy for hours.  But, it can be chewed, and she has destroyed a number of them.  Considering that, I like the internal construction.  The gigglers are inside very hard tubes, so although she managed to get inside the rubber exterior, she had a much harder time with the insides and it was easy to take the tubes away from her once she had exposed them.  She still likes the ball and carries it around like a prize.