The IS-2Sh (IS-M) was a project for the significant modification of the IS-2 proposed by N. F. Shashmurin at Kirov Factory No. 100 in early 1944. The design featured a long-barrel 122 mm gun and a rear placement of the fighting compartment. The project was discontinued in favor of the IS-6 (Object 252).
The technical characteristics shown are for the Siege mode
Characteristics are specified for a vehicle with crew members trained to 100%.