The primary role of the Type 42 destroyers was providing air defense for the fleet. With their long-range sensors, the ships could also act as radar pickets, sailing ahead of a task group. HMS Southampton was the eighth ship originally destined to be a 16-ship class — two of these ships have been exported to Argentina. The type 42 comprised eight Batch 1 vessels, four Batch 2 and four Batch 3 Stretched Type 42.