T1 Heavy Tank
The T1 Heavy Tank is one of the most enjoyable vehicles to play and belongs to a robust USA Heavy tank line. However, despite having decently rounded and thick frontal armor, the rear of the T1 Heavy might as well be made of paper.
Any time you spy this Tier 5 Heavy on the battlefield, try to shoot it from behind, as its rear armor is a measly 46 mm thick with side armor that isn't much better. Unfortunately for the T1 Heavy Tank, having such thin side and rear hull armor does not bode well for its engine, fuel, and transmission, which are all located on its backside.
If for some reason you cannot pierce its thin armor, this is one situation where using a HE round is ideal. Penetrating the rear armor of the T1 with an HE round could result in some impressive fireworks.