SM U-85 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-85 was engaged in the naval warfare and took part in the First Battle of the Atlantic. Initially U 81 to U 83 had one 10.5 cm gun with 140-240 rounds. U 84 - U 86 on the other hand had two 8.8 cm guns. In 1917 U 84 - U 86 were refitted with a single 10.5 cm gun (240 rounds)