Your mastery makes the most of your armor.

Prerequisite(s): Armor Focus, base attack bonus +6, proficiency with selected armor.

Benefit(s): The armor check penalty of the selected armor decreases by 1 (to a minimum of 0). You also use your character level in place of your base attack bonus for the purpose of armor mastery feat prerequisites.

Special: You can gain this feat multiple times. Its effects do not stack. Each time you take the feat, it applies to a new type of armor.