You are proficient with heavy armor.
Prerequisite: Armor Proficiency (Light), Armor Proficiency (Medium).
Benefit: When the character wears a type of armor with which the character is proficient, the character gets to add the armor’s equipment bonus to his or her Defense.
Normal: A character who wears armor with which he or she is not proficient takes an armor penalty on check involving the following skills: Balance, Climb, Escape Artist, Hide, Jump, Move Silently, and Tumble.
Also, a character who wears armor with which he or she is not proficient adds only a portion of the armor’s equipment bonus to his or her defense.