The machine itself (IS-M) is better known as the IS-2Sh and was first introduced in WoT Blitz. The heavy tank IS-2SH is a proposal for the modernization of IS-2, proposed by N.F. Shashmurin at the factory number 100 in early 1944. The project provided for the relocation of the combat compartment, as well as the installation of a 122-mm long barrel gun. The project did not receive further development, as the development of the IS-6 tank (Object 252) began.
Here we have Renders, Armor layouts and stat screen shots with English overlay.
Source WoT Express