 Although Lockheed submitted improvements including vertical launch systems, 76 mm guns, and advanced combat systems and sensors, the Navy opted to keep the 57 mm gun, not add a vertical launch system, and chose to add an upgraded 3-D radar.Other changes included installation of an unspecified over-the-horizon missile, Mark 38 25 mm guns, a torpedo countermeasures system, a multifunction towed array system, installation of the SeaRAM launcher, an upgraded countermeasures decoy system, an upgraded electronic warfare system, armor added to vital spaces, and improved signature management.The SSC will focus in SUW and ASW with these additions, as well as retaining all other features of their mission packages; the SSC is not required to perform MCM, which will continue to be handled by the LCS.