The code that identifies a range of invoice folios (numbers) issued by SII (Servicio de Impuestos Internos). Each time the folio range is consumed, suppliers must request a new CAF from SII. The CAF information is presented within the TED in each DTE (Documento Tributario Electrónico) and includes data such as supplier information (e.g., RUT (Rol Único Tributario) number), DTE type, Folio range, CAF issuance date, and SII digital signature (FRMA (Firma Folio)).