The angle of armour has a lot to say to the protection of a tank, both in real life, and in SB. A thin armour plate at a steep angle will have a high LOS thickness. The general rule is, any armour plate at a 60 degree angle will have twice the protection of a plate at a 0 degree angle. In SB, this has a various effects. A tank on a backward slope, will have slightly higher LOS thickness on the turret front areas and glacis, while the lower front hull will have slightly less LOS thickness. The effect is more pronounced depending on how the armour of the individual tank is angled. This also means that hitting the usually thin side armour of a tank, might not cause a penetration for rounds that would penetrate easily at a 90 degree angle.