Check Penalty
The Check Penalty is a property of Armor and Shields that applies a penalty to certain Active Skill checks. If you are wielding both Armor and a Shield, the sum of the check penalty from both items applies. Whether or not the Check Penalty applies is indicated on each Active Skill's page.
Generally speaking, the heavier the armor or shield, the greater the Check Penalty. In other words, it is difficult to perform certain tasks, such as Climbing, Jumping, or Swimming while utilizing heavy or bulky equipment. A character can remove their check penalty at any time, if they remove the armor or shield they are utilizing before attempting the skill check.