The Icelandic+ Lamb Horn with Marrow is made of keratin - not a bone! Dogs instinctively want marrow in their diets. Their primal taste buds love it. Packed full of healthy nutrients, vitamins, calcium & protein, Lamb Horns with Marrow provide hours of chewing enjoyment and help keep dog's teeth clean. Plus, you have peace of mind knowing it's been cleaned, boiled & baked within FDA, USDA, EU & MAST standards & regulations. This treat is 100% Viking & 100% natural with no additives, preservatives or supplements.