My never chew on it, they just lick the stuff out and roll it around and play with it. I don't put any solid treats in it, they just don't like it. I either put some cheese from a spray can in it or I stuff it with canned dog food and they love it and it takes them awhile to get all of it out. I love watching them getting the stuff out of the kong, they just have a ball!! They don't like peanut butter though, or any solid food like liver treats, I guess it is too hard for them to get it out. I would also on an occassion fill the kong up with koolaid and freeze it so they would get a kong popsicle and they loved it too, especially when they were teething.
