190330-N-CE622-0198 ATLANTIC OCEAN (March 30, 2019) The Arleigh Burke-class guided-missile destroyer USS Lassen (DDG 82) fires a Mark 38 25 mm gun system during a sustainment exercise. Lassen is a part of the Harry S. Truman Carrier Strike Group participating in SUSTEX, an integrated, comprehensive exercise designed to ensure HSTCSG is ready to meet all mission sets and carry out sustained combat operations from the sea. (U.S. Navy photo by Mass Communication Specialist 3rd Class Katie Cox/Released)