Hi Felix, may be a mix of both type II and VII may have enjoyed better success, but the type II were built as a training boat, used initially in combat due to the small number of U-boats available in the early months of the war. The decision to put U-boats in the Med, was made by Hitler, the Italian navy failing to dominate that sea, with the German Afrika Korps in Africa needing regular supplies, Hitler had little choice but to deplete the U-boats in the North Atlantic, and try to protect German convoys sailing to African ports, as well as bring Malta to surrender. john