Our dog loves these but they are definitely not indestructable!
Our dog goes absolutely crazy for kongs, from the moment you walk in the door with it in your bag, he can smell the rubber and wants the kong.
He is a a staffie and we've found that the XXL Extreme Kong to be the best choice as he destroys toys with ease, he seems determined to destroy any toy he's given... We have to ration his use of the Kong to ensure it lasts longer. If your dog isn't as crazy about destroying toys as ours and you're looking for a strong toy, I think this is the kong for y