Two magnetic tapes, in their cases, that were used on the PDP-8 computer at the Nuclear Power Demonstration (NPD) reactor dedicated to control, monitor and record activities of the fueling machine. The tapes, manufactured by the Digital Equipment Corporation (DEC), are approximately 10 cm in outer diameter. One of the tapes is marked as having been used 22 September 1986, approximately a year before the shutdown of the NPD reactor.