Increases P. Def. by 1 for A-grade armor and accessories. Increases by 3 starting from +4. It can safely be enchanted up to +3. For one-piece armor, it can safely be enchanted up to +4. If enchanting fails, the item will not be crystallized but the enchant value will be reset to 0. When armor is enchanted above +4, HP also increases depending on the enchant value.