Neck Guard

Source Advanced Race Guide

Made from hardened leather reinforced with a band of metal, this collar protects the wearer against vampire bites when worn around the throat. It provides a +1 armor bonus to AC against vampire bites or similar attacks that specifically target the wearer’s throat. Unlike most armor bonuses, the neck guard’s +1 bonus stacks with the armor bonus of light or medium armor, but it provides no additional bonus when worn with heavy armor.