This is the Zvezda 3608 kit in 1/35 scale, of the ‘Russian Heavy Tank, KV-2’.
76-mm tank gun L-11, mounted on KV, didn’t prove to be sufficiently powerful to fight Pillboxes and other fortifications. A new KV-2 tank, fitted with the M-10 152-mm howitzer in the turret, was designed for the destruction of defensive military fortifi cations.
The production of the KV-2s started in 1940 and soon after the start of WWII in Russia the production of the vehicles was phased out as this single-purpose tank was an exorbitant luxury in the severe conditions of the initial period of the war.
Source: Zvezda website