This propeller, one of four, was installed on a B-29 Super Fortress, the largest and deadliest American heavy bomber of World War II. The B-29 effectively ended World War II by delivering atomic bombs on Hiroshima and Nagasaki in August 1945. Two of the four blades of this particular propeller were installed on FIFI, the Commemorative Air Force's air worthy B-29, the only Super Fortress in the world still flying.