The American Pit Bull Terrier (APBT) is a purebred dog breed recognized by the United Kennel Club (UKC) and American Dog Breeders Association (ADBA), but not the American Kennel Club (AKC). According to the ADBA, the American Pit Bull is prescribed to be medium-sized and has a short coat and smooth well-defined muscle structure, and its eyes are to be round to almond-shaped, and its ears are to be small to medium in length, typically half prick or rose in carriage. The tail is prescribed to be slightly thick and tapering to a point. The American Pit Bull Terrier is a working dog, and is suitable for a wide range of working disciplines due to their intelligence, high energy, and endurance. In the United States they have been used as search and rescue dogs, police dogs performing narcotics and explosives detection, Border Patrol dogs, hearing dogs to provide services to the deaf, as well as general service dogs.