This is a transporter-storage cradle for the Mark 2 reentry vehicle (RV) that carried the nuclear warhead atop the U.S. Air Force Thor intermediate-range ballistic missiles and early test versions of the Atlas intercontinental ballistic missile in the late 1950s and early 1960s. The Mark 2 RV had a copper blunt nose and is the only operational "heat sink" RV the United States employed. It protected the warhead from the tremendous heat generated during reentry into the Earth's atmosphere by absorbtion. The manufacturer of the transporter-storage cradle is unknown. It was transferred by the U.S. Air Force Museum to the museum in 1975.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.