American Mastiff is large dog breeds originating from the United States. They are used as working dog breeds. it has heavy bone structure and athletic built. it grows as tall as 28-36 inches and weighs between64-91 kg. its gait is far reaching and effortless. Its coat is smooth and short. It has an air of elegance and regality. Its affectionate towards children and calm towards strangers. Its protective and brave. They make excellent companion dogs.