Object is a large metal panel bearing 20 BNC connectors and one multi-pin male connector. It has sockets for 12 vacuum tubes, of which 7 are populated. A card attached to the front with celephane tape reads "NR3701 - Box 4 - #11, 842 Parity Register #25" agrees with the black label on the wire side, but disagrees with the printed information in the upper left corner. The printed information is partially obscurred by black adhesive residue.
