The SU-152 followed the same, fully enclosed casemated design as most other Soviet self-propelled guns. The fully armoured hull was divided into two compartments: a fighting compartment for the crew, gun, and ammunition in the front of the hull, and the engine and transmission separate in the rear. The hull was welded from rolled armour plates of different thickness — 75, 60, 30 and 20 mm. The front hull and superstructure armour plates were sloped for better vehicle protection; side armour was vertical. Lower front hull and rear armour plates were cylindrical, and were quite complex in their method of production. The ML-20S gun-howitzer was mounted slightly to the right of centre with a limited traverse in a range of 12 degrees. Three of the crew were to the left of the gun: driver to the front, then gunner and last the loader. The vehicle commander and breech mechanism operator were to the right.