American Staffordshire Terrier

The American Staffordshire Terrier, also known as the AmStaff, is a medium-sized, short-coated American dog breed recognized by the American Kennel Club, but not the United Kennel Club, which instead allows American Staffordshire Terriers to be registered under the American Pit Bull Terrier breed. The American Staffordshire Terrier stands 18–19 in (46–48 cm) tall and weighs between 40–70 lb (18–32 kg).

Source: Wikipedia — American Staffordshire Terrier (CC BY-SA 4.0)