The UNIVAC 490 was a 30-bit word magnetic-core memory machine with 16K or 32K words; 4.8 microsecond cycle time made by UNIVAC. It was a commercial derivative of the instruction set that had been developed for the AN/USQ-17 by Seymour Cray for the US Navy. This was the last machine that Cray designed before leaving UNIVAC to join the early Control Data Corporation.
Univac Federal Systems would further developed this system into the AN/USQ-20 for the United States Navy. That system was the heart of the Naval Tactical Data System which pioneered the use of shipboard computers for air defense. The military version went by a variety of names: UNIVAC 1232,[1] AN/USQ-20, MIL-1206 and CP642.