5c blue 'Momotombo' postal stationery envelope (H&G B45) used with superb strike of ADMINISTRACION DE CORREOS DE BOACO oval cancel dated NOV 11 1904. Addressed to MANAGUA with large circular CARTERO No. 4 - 10 A.M. MANAGUA marking on front and MANAGUA oval arrival mark on reverse. Trimmed approx 1cm at left but a rare origination.