Air Mail cover 1917 (21 Oct.) envelope flown from Fiume to Pola and re-addressed to Laibach, showing previously unrecorded three-line "K.u.K./Marinestationskommando/Feldpost 406" cachet in red, with faint F.P.O.406 and "K.U.K. MARINEFELDPOSTAMT/POLA" c.d.s. adjacent. Fine

細節
Air Mail cover 1917 (21 Oct.) envelope flown from Fiume to Pola and re-addressed to Laibach, showing previously unrecorded three-line "K.u.K./Marinestationskommando/Feldpost 406" cachet in red, with faint F.P.O.406 and "K.U.K. MARINEFELDPOSTAMT/POLA" c.d.s. adjacent. Fine