German 10pf + 10pf carmine 'Reichspost' postal stationery reply card (H&G 48), the reply half correctly used back from Guatemala to Germany datelined 'Montecristo 17 April 1901' with large oval 'MONTECRISTO - TUMBADOR' company's handstamp on front with OFICINA POSTAL DE TUMBADOR cds dated APR 19 1901. Addressed to BREMEN with octagonal GUATEMALA CITY transit cds dated ABR 25 1901 on front. Reverse has the original boxed 'ADMN DE CORREOS DE SAN MARCO arrival mark from the outbound card. An incredible item of exceptional rarity.