Small parcel label from a coffee sample bag with 'MUESTRA SIN VALOR' and 'MUESTRA DE CAFÉ COFFEE SAMPLE' handstamps on front franked on reverse with 1935 1c scarlet & brown and 4c carmine & blue and 3 x 1939 1c olive green with '1939' overprint (SG 294, 297 & 399) tied by SERVICIO INTERNACIONAL CORREOS GUATEMALA C.A. cds dated 1 JUL 1939. Addressed to UK with LONDON F.S. arrival mark on front. An unusual use and rate.