The difference between an American XL bully and an XL bully is that the American XL bully is a type of American bully, while the XL bully is a size category of the American bully. The American bully is a mixed breed that originated from crossing various bully breeds, such as the American Pit Bull Terrier and the American Staffordshire Terrier.
The American bully has four types: classic, standard, pocket, and extreme³. The American XL bully is a variation of the standard type, but it is taller, more muscular, more massive, and bulkier. The XL bully is a size category that applies to any American bully that is over 20 inches at the withers for males and over 19 inches for females.
Therefore, an American XL bully is also an XL bully, but not all XL bullies are American XL bullies!