This is a model of unknown scale of the Polaris A-3, the third and last version of America's first generation submarine-launched ballistic missile. A two-stage solid-fuel missile, the A-3 had a range of slightly less than 3,000 miles and carried up to three nuclear warheads. It saw service in both the U.S. and British navies from the 1960s into the 1980s. The model's manufacturer is unknown.
John and Cynthia Heyde donated it to the museum.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.