cover 1900 (Apr) U5 complete with enclosed letter, from Narva, Russia bearing 1k., 2k. and 7k. (on reverse), to a Private with "Prince Alfred's Guards Mounted Infantry, Orange Free State", and bearing a Z.A.R. Officially Resealed label endorsed, in red, "Geopend onder Krygswet" (Opened under Martial Law). The letter has also been endorsed, in red, "Gezien" and signed. Attractive and most unusual.