In the last two years my pets have demolished at least eight of these Roll A Nests size Large. The first thing our pets would do was chew through the weaving so the nests fell apart. These balls cost around $14.00 each at Pets Mart; but, we kept buying them because the pets loved playing in them and on them. Now, as soon as we get a new ball, my husband weaves a thin wire through-out the ball. It lasts much longer with that refinement. I was very pleased to see them at Pet Mountain because they cost so much less! Thanks so much for helping our budget!