"To GBTU TU chief, Engineer-Colonel comrade Blagonravov
I report that the Kirov factory design bureau is completing the development of an SPG on the chassis of the Kirovets-1 tank.
The hull is characterized by the following:
- Lower front plate: 120 mm at 55 degrees
- Cheek plates: 120 mm at 50 degrees
- Upper side plates: 90 mm at 45 degrees
- Upper rear plate: 60 mm at 40 degrees
- Lower side plates: 75 mm at 60 degrees
- Vertical side plates: 90 mm
- Floor and roof: 20 mm
The overall height of the SPG is 140 mm lower than the SPG on the IS chassis.
To allow for normal working conditions, the driver's compartment is moved out of the front of the vehicle and to the left front part of the fighting compartment, raised by 600-700 mm, which will be supported by a floor for the driver that will hold the levers, pedals, and the driver's seat.
The driver has two positions:
- Battle: the driver will look through a MK-4 mirror periscope.
- Driving: the driver will look out of the hatch installed in the roof.
The seat will have two positions to allow this.
Due to the driver's station being moved to a new place, the control linkages will have an additional stage to connect the levers and pedals on the raised floor and the linkages on the floor of the vehicle.
The transmission, engine compartment, and running gear are the same as the Kirovets-1 blueprints.
Production of the first prototype of the Kirovets-1 hull began at the factory on February 1st.
Representative of the GBTU, Engineer-Lieutenant Colonel Markin.
February 10th, 1945"