The Sejong-Daewang, the first of South Korea's new KDX-III-class destroyers was commissioned on 22 December 2008. The highly advanced, 10,000-ton (full load) destroyer launched on 25 May 2007 was built by Hyundai Heavy Industries of Ulsan. At least two additional units of the class are also being built, with the second destroyer expected to join the fleet in 2010 and the third in 2011. An option for three others may also be exercised. Though similar in design to the U.S. Navy's Arleigh Burke Flight IIA and Japan's Improved Kongo classes of destroyers, the Korean Sejong-Daewang class is more heavily armed and carries more vertical-launch tubes than either warship. During 2009 the Sejong-Daewang is expected to conduct extensive sea trials before achieving full operational capability in 2010.