Despite the name, Moon bones aren't actually bones. It is 100% air dried beef cartilage. A long-lasting chew which is softer and more flexible than bone, it also won't splinter. Cartilage is also naturally full of Glucosamine and Chondroitin which are fantastic for keeping joints healthy! Works as a great 'natural toothbrush' cleaning the teeth naturally whilst also satisfying their natural urge to chew.