The Type 704 Rhön-class tankers are a series of replenishment oilers used by the German Navy to provide underway replenishment for its ships at sea. The two vessels in the class, Rhön and Spessart, were originally constructed for Libya by Kröger Shipyard in Rendsburg, West Germany as bulk acid carriers. They were acquired by the West German Navy in 1976 for conversion and entered service in 1977. The two ships are crewed by civilians. In 2019 it was announced by the German Navy that the ships are planned to be replaced in 2024.