This is the second version of this model which is in slightly higher resolution than the pervious version.
According to Wikipedia: "The Phalanx CIWS is a close-in weapon system for defending against anti-ship missiles. It was designed and manufactured by the General Dynamics Corporation, Pomona Division (now a part of Raytheon). Consisting of a radar-guided 20 mm (0.79 in) Gatling gun mounted on a swiveling base, the Phalanx is used by multiple Navies around the world, namely the Royal Navy and the United States Navy on every class of surface combat ship, by the United States Coast Guard aboard its Hamilton-class and Legend-class cutters and the navies of 16 allied nations."