"Haha! Who's in this tin can?
Heavy Armor is a low-tier Equipment (acquired after unlocking the Skill of the same name) which can be used in one of three equipment slots available per Trooper. It reduces Damage sustained by 1 (no matter which body part is hit) and reduces Speed by 20%. is presumed to negate the damage reduction.
This skill's damage reduction effect can combine with the Bulletproof Vest or Full Metal Balaclava. It is not yet explicitly confirmed, but it was suggested that this item (unlike Bulletproof Vest or Full Metal Balaclava) is not accounted as Armor. If this is true then the Heavy Armor may still have effect when fighting troopers with skills such as Armor-Piercing Shells.
A reasonable upgrade for long-ranged troopers with no need to run about. The negative effect of the skill can easily be negated by speed-augmenting abilities. However, the wearer isn't protected from Killshots.