The Flying W Farms American Mastiff (TM) was developed over many years of selective breeding by Fredericka Wagner of Flying W Farms, Piketon, Ohio. The goal was to develop a dog that had the size, temperament, disposition, and the appearance of the Mastiff, but with fewer health problems, and a much dryer mouth than other mastiff breeds. This was accomplished by crossing the English Mastiff with the Anatolian Mastiff during the early development of the breed.

The American mastiff is a large, massive, powerful dog with a moderately broad head, dropped ears, kindly wide set eyes, of brown or amber color, the darker the better. Powerful neck, wide, deep chest, muscular back. Tail is wide at the root, tapering to the end, hanging straight in repose, forming slight curve. The overall appearance should be of proportions slightly longer in body than in height.

They display a balanced combination of grandeur, good nature, and gentleness. Dignity rather than gaiety. They are neither shy nor vicious. The well-trained Fling W Mastiff is calm, controlled, and confident. Understanding, patient, and loving with their family, especially children. They are aloof towards strangers. A well-socialized American Mastiff is friendly yet sensitive and alert to changing situations. They are not aggressive by nature but will defend their family if necessary. They respond to threats with judicious warnings and courageous action if needed

Height at maturity is typically 32 to 36 inches for males. Males average weight is 160 to over 200 pounds. Height at maturity for females is typically 28 to 34 inches. Females average between 140 and 180 pounds. Larger or smaller for both males and females is acceptable provided the dog is in good proportion and structurally balanced.