German ship's mail, Marineschiffspost MSP14 - Feldpost card with cancel of the Dampfer General, a support ship for the German forces in Turkey during WWI, among other duties forwarding mail from other units who didn't have their own on-board post offices, in this case Sonderkommando (Salamis?). A bit worn, in Bedarfserhaltung / commercially used, good condition, as per scans.