There is a piece of masking tape on one side of the cube with information about a test. The test date is given as 2 March 65. On two sides of the cube there are "memory diode matrix" boards. On another side there is an array of resistors.
Scientific Data Systems (SDS)
Santa Monica, Calif.
Stamped into a label on the side frame.
SDS part number stamped into a label next to the big connector
Stamped onto a label next to the the big connector
Ferroxcube serial number on a label on the frame at the side.