Armoured Hits scored by a weapon with the Light trait against a model with the Armoured special rule count their AP as 0. In addition, a model with the Armoured special rule may re-roll failed Save rolls made against Hits scored by a weapon with the Light trait.
Invulnerable Save (X) A model with the Invulnerable Save (X) special rule gains an additional Save characteristic equal to the number shown in brackets, referred to as an Invulnerable Save. Invulnerable Saves are not modified by a weapon's AP characteristic.