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Armor Check Penalty: Any armor heavier than leather hurts a character’s ability to use some skills. The penalty applies to hide, move silently, parry, pick pocket, set trap, and tumble. A character's encumbrance (the amount of gear carried, including armor) may also apply an armor check penalty.

If a character is wearing armor and using a shield, both armor check penalties apply.

Type of Armor or Shield Base AC Armor Check
Penalty
Max Dex
None, Clothing 0 None -
Padded armor 1 None +8
Leather armor 2 None +6
Studded leather armor, Hide armor 3 -1 +4
Chain shirt, Scale mail 4 -2 +4
Chainmail, Breastplate 5 -5 +2
Splint mail, Banded mail 6 -7 +2
Half plate 7 -7 +1
Full plate 8 -8 +1
Small shield 1 -1 -
Large shield 2 -2 -
Tower shield 3 -10 -