After going through probably hundreds of dog balls for my 2 cattle dogs, some lasting a few weeks and some only a day, in desperation I tried the KONG Balls. Although initially they are more expensive than others they are the most cost effective balls I have ever purchased. I have had these now for over a month and my dogs have been unable to put a mark on them. They are not destructive dogs , the other balls just fell apart from normal catch and play. They love the bounce of the balls and leap in the air to catch them. Happy dogs and Happy owner. Only balls I would now recommend.