Built as reefers in 1937, the four sisters, Ramb I-IV were all taken into war service. Ramb I & Ramb II became raiders but were handicapped by their short range. Ramb II ended her cruise in Japan and was chartered to the Japanese. Scuttled by the Italian crewe in 1943, she was refloated by the Japanese and sunk by the USAF in 1945.

Ramb III became an auxiliary escort vessel but was torpedoed by HMS Triumph in harbour at Benghazi. Repaired at Trieste, she was seized by the Germans, becoming "Kiebitz", a minelayer. She survived one of her own mines exploding and bombing to become the Yugoslav Training Ship "Galeb" and was still in service in the 1990s!

Ramb IV became a hospital ship and was captured in April 1941 by the British. Bombed and sunk by German aircraft off Alexandria in 1942.