This object has a metal frame, open on both sides, and a door on the back. The front two thirds of the frame contain a roll-out unit with two hinged card cages. The cages are filled with IBM modules. At the top there is an orange add on bracket with one screw protruding from the middle. The back third of the frame is for cabling.
International Business Machines (IBM)
Entched into the manufacturer's plate in the top right corner of the front of the machine.