This object is not on display at the National Air and Space Museum, it is either on loan or in storage.
Country of Origin: United States of America
3-D Test: 17.8cm (7 in.)
Other (Face): 15.2cm (6 in.)
Physical Description:6in. diameter x 7in.; black aluminum case; 5.1/25in. diameter face.
Inventory number: A19890623000