KV-13

The KV-13 (Object 233) was an experimental Soviet medium tank created during World War II. It was developed on the KV-1 chassis in the SKB-2 design bureau of the Chelyabinsk Kirov Plant in late 1941 — early 1942, as a "universal" tank, intended to replace the production of T-34 medium tanks and KV heavy tanks at the same time.

The first prototype of the KV-13 was made in the spring of 1942, but in the fall of that year its tests showed its lack of mechanical reliability and the need to strengthen the armour and the need to equip with the new three-seat turret. While in December 1942 began production of two modified prototypes in design which takes into account these requirements, work on the KV-13 as a medium tank was discontinued in favor of continuing the T-34 manufacturing. The further development of the project using two modified KV-13 prototypes led to the creation in 1943 of the IS-1 heavy tank.