"Report on new types of tanks and SPGs according to reports by prisoners of war and armoured staff reports as of July 20th 
- The suspension, engine, and transmission of the modernized T-4 tank are the same as the regular tank of this type.
- The hull has the following changes:
- The front of the tank has the following applique armour:
- The lower front plate and sloped front plate are protected by track links, held onto the armour by clamps or bolts. The upper front plate of the tank is protected by a 20 mm thick armoured plate, positioned about 200 mm in front of the main armour, and attached by welding.
As such, the T-4 tank uses spaced armour.
- The sides of the tank are protected by 4-4.2 mm thick plates, four plates per side. Each plate hangs on three carriers, bolted to the side of the tank and the fenders. The bent ends of the carriers fit into slots of the 8 plates, and are additionally attached by one bolt that is screwed into a bracket welded to the upper carrier.
The side plates are made up of very soft armour or iron. The edges are cleanly finished. The plates hang outside of the suspension, about 500 mm away from the sides.
- The tank turret is protected in a similar way (aside from the gun mantlet) with 8 mm thick armoured plates, affixed to carriers, which are welded to the turret. The spacing between the plates and the main turret armour is 380-480 mm. The rear of the turret (and the stowage box) is protected by 4-4.2 mm thick plates, similarly affixed to the turret armour with the same spacing.
Like the side armour, the material is either very soft armour plate or iron. The edges are also cleanly finished.
- The rear of the hull has no applique armour."