This tank mechanic: you get stacks with every shot directed to the enemy tank (doesn't matter if you penetrate it or not).
More stacks you get, better DPM you have.
It is an extremely powerful tank for people who know how to play aggressively with not the best armoured tank.
It is similar to T110E5 in a sense that you need to block your cupola so enemies won't penetrate it.
Hard tank to master.