Cover franked with 1903 12c slate and 1905 1c on 2c carmine 'Provisional' SURCHARGE issue (SG 491 & 523) tied by dumb 'S' cancel with large oval CORREOS DE EL SALVADOR NEGOCIADO DEL EXTERIOR cancel of SAN SALVADOR dated FEB 20 1906 alongside. Addressed to USA with arrival cds on reverse.