Every BattleMech has 8 chassis locations where armor, internal structureand components are tracked. These locations are:
Left Arm
Head
Right Arm
Left Torso
Center Torso
Right Torso
Left Leg
Right Leg
Additionally, armor damage is tracked in the rear center, rear right and rear left torso locations. When incoming damage hits one of these locations, it is applied first against the armor. If the armor is penetrated, damage is done to the internal strucutre and potenially one or more of the internal components within that location.