The medal's obverse bears portrait of elderly FDR, facing right. Around, FRANKLIN DELANO ROOSEVELT - FOURTH INAUGURATION 1945; signed over shoulder at left, JO DAVIDSON
The reverse bears allegorical ship under full sail. Around, THOU TOO SAIL ON O SHIP OF STATE - SAIL ON O UNION STRONG AND GREAT
The circular medal measures 44.4mm in diameter and was struck in bronze by the U.S. Mint. I do not know the medal's mintage.