Postal Stationery item

Quality: PWS

1923, Stibbe nr RU 15, 15c + 15c on 5c + 5c green, sent from Postes Militaires (military field post office) July 9, 1923 to Brussels / Belgium, with Belgian label "Inconnu / onbekend" and Belgian postman cachet "330 D", very interesting and scarce, vf