Raytheon Company, Tucson, Arizona, is being awarded a not-to-exceed $161 million contract modification for MK15 Mod 31 SeaRAM systems in support of LCS 6 and 8 and Japan's DDH 2405 helicopter destroyer, as well as Phalanx Close-In Weapon System (CIWS) Block 1B class "A" overhauls, and land-based Phalanx Weapon System class "A" overhauls. CIWS is a fast-reaction terminal defense against low- and high-flying, high-speed maneuvering anti-ship missile threats that have penetrated all other defenses. Operating either autonomously or integrated with a combat system, it is an automatic terminal defense weapon system designed to detect, track, engage, and destroy anti-ship missile threats penetrating outer defense envelopes. Phalanx CIWS is currently installed on approximately 152 Navy and 14 Coast Guard ships and is in use in 23 foreign navies. The Naval Sea Systems Command, Washington Navy Yard, D.C., is the contracting activity.