This paper model is a IS-3 (Iosif Stalin-3, Rus. ИС-3), a battle tank of the Iosif Stalin heavy tank series, the papercraft created by World of Tanks website. It was developed by LKZ and was not taken in service. There are 2 tanks known as IS-3. IS-3 (Object 244) was an IS-2 rearmed with the long-barrelled 85mm cannon (D-5T-85-BM). It was developed by LKZ and was not taken in service.
IS-3 (Object 703) was developed in late 1944 by ChTZ. This tank had an improved armour layout, and a hemispherical cast turret which became the hallmark of post-war Soviet tanks. While this low, hemispherical turret may have improved protection, it also significantly diminished the working headroom, especially for the loader. The low turret also limited the maximum depression of the main gun, since the gun breech had little room inside the turret to pivot on its vertical axis.
As a result, the IS-3 was less able to take advantage of hull-down positions than Western tanks. The IS-3's pointed prow earned it the nickname Shchuka by its crews. It weighed slightly less and stood 30 cm lower than previous versions. Wartime production resulted in many mechanical problems and a hull weldline that had a tendency to crack open.
The IS-3 came too late to see action in World War II. The tank saw no action against the Germans, although one regiment was deployed against the Japanese in Manchuria. Starting in 1960, the IS-3 was slightly modernized as the IS-3M, in a manner similar to the IS-2M. [Source: wiki]
You can download this tank papercraft here: Iosif Stalin-3 (IS-3) Tank Free Paper Model Download