My 3 mo old puppy is obsessed with the Whimzees Brushzees. A co-worker got me one as a gift and he went crazy for it. You can buy them individually at PetCo or PetSmart. They are shaped like a bone with a tooth on the end. I wanted to buy a bulk bag but the reviews on Amazon indicated they were old/stale so I'll stick to buying individually I guess. It occupies my puppy for a solid 20 minutes and doesn't break off into pieces, at least not the two he's had so far.