Plate Armor
From Crusaderkings
Plate armor is heavy armor which covers most of the body, granting superior protection. It is heavy and expensive however, so its use is restricted to the heaviest troops: knights and heavy infantry.
Quilted Coat (Level 1): Armor 9
Scalemail (Level 2): Armor 12
Half Plate (Level 3): Armor 15
Platemail (Level 4): Armor 18
Full Plate (Level 5): Armor 20