I bought a large Jive ball for my two year old Italian Mastiff (Cane Corso). After two weeks of heavy chewing on it he has been unable to harm it more than a few scratches on the surface. To date he has destroyed every toy that's we've tried with him, countless so called "indestructible" toys were destroyed in minutes. This guy crushes bones like ice cubes, you know those huge bones you see at the pet shop, its a cow femur, they last about a month. The only thing that will last are items you have to play with and then put away, like ropes or a frisbee, or things he loses interest in, like a Kong. I was so skeptical when I got this, I thought there was no way it would last, but it seems like it will last for a while. I don't think any dog can damage this thing, if there is, I want to see it. Its made from a super solid rubber but still flexible to have a decent bounce, it takes very little force to bounce it high enough to return to your hand.