7 in. Center bones are one of the top three Jones favorites. Most of our centers will have succulent marrow in the center of the bone along with tasty meaty pieces left on the bone. Each of our center bones are dipped in natural liquid smoke and then slowly roasted. They are USA all-natural beef femur bones with no artificial ingredients. These are best for medium to large size dogs. All Jones products are 100% grown and made in the USA.