The SU-85 was a Soviet casemate-style self-propelled gun used during World War II, based on the chassis of the T-34 medium tank. Earlier Soviet self-propelled guns were meant to serve as either assault guns, such as the SU-122, or as tank destroyers; the SU-85 fell into the latter category. The designation SU-85 is derived as follows: 'SU' stands for the Russian: Samokhodnaya Ustanovka - self-propelled carriage, while "85" signifies the bore of the vehicle's armament, the 85 mm D-5S gun.
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