The Cover features a Fi 376d (rare dark brown-red shade) stamp, form II, type 2, together with a Fi 380b (carmine-red) stamp.
Fi 380b shows perforations added locally.
Fi 376d was issued in 09/1945 as an overprint on Fi 342Vd (rare dark brown-red shade) with a new nominal value.
Types 1 & 2 refer the positioning of the decimal point in the new value. The cover was sent on 8th December 1945 from Bielsko Biala, Poland.
[Fi 342 (Polish Eagle) was issued in 13/09/1944. Known as the ‘Goznak’ issue, the first supply was sent from Moscow to Lublin, Poland, which had been liberated by Soviet forces on 24th July 1944 and which became the temporary headquarters of the Soviet-controlled Communist Polish Committee of National Liberation established by Joseph Stalin]