This is: a souvenir sheet of 3 stamps from Poland, issued in December of 1948. On the three stamps are Franklin Roosevelt and Polish national heroes Pulaski and Kosciusko. The sheet, C26d, is Mint Never Hinged and numbered 08053 in the lower left.
Check the scans for details. The item "Poland 1948 Souvenir Sheet 1948 C26d Airmail MNH Roosevelt Kosciusko Pulaski" is in sale since Saturday, June 19, 2021. This item is in the category "Stamps\Europe\Poland".
The seller is "americasstampstop" and is located in Berkley, Michigan. This item can be shipped worldwide.