Share Armor

Your ally may treat their guard and block as if they were wearing your armor and shield until the end of the current creature’s turn. If multiple creatures of the same type move on the same initiative, it lasts through all of their turns.

Any temporary increases to the guard/block of this armor (such as through reinforce armor) is not transferred over. Any increases from armor plates or cloak are also not carried over. (But the target's own plates or cloak may apply.)