General Dynamics National Steel and Shipbuilding Co. (NASSCO), San Diego, California, is awarded a $500,000,000 modification to previously awarded contract N00024-16-C-2229 to award long-lead-time material in support of T-AO 211 and 212. Work will be performed in Iron Mountain, Michigan (27%); San Diego, California (22%); Beloit, Wisconsin (14%); Columbia, South Carolina (8%); Arlington, Virginia (7%); Chelsea, Alabama (4%); Walpole, Massachusetts (4%), New Orleans, Louisiana (2%); and various other locations less than one percent (12%), and is expected to be completed by June 2027. Fiscal 2022 shipbuilding and conversion (Navy) funds in the amount of $500,000,000 will be obligated at time of award and will not expire at the end of the current fiscal year. The Naval Sea Systems Command, Washington, D.C., is the contracting activity.