Full definition
Mexican colloquial term for a fastening bolt, especially a wheel stud on vehicles. "Birlo de seguridad", "birlo antirrobo", "birlos de 12mm." High-volume search term specific to the Mexican automotive and industrial market. Not used in Argentina (where "espárrago de rueda" is standard) or Chile/Peru ("espárrago" or "perno de rueda"). Including "birlo" in digital catalogs targeting Mexico captures searches that competitors systematically overlook.