An armor mask is not a widely recognized term or concept. However, based on the two words that make up the phrase, it's possible to speculate about what it might refer to.
Armor typically refers to protective clothing or equipment worn by soldiers, knights, or other individuals in combat or other dangerous situations. Armor can take many forms, including helmets, breastplates, greaves, and gauntlets, and is often made of materials such as metal, leather, or hardened fabrics.
A mask, on the other hand, is a piece of material or equipment that covers the face or head. Masks can serve a variety of purposes, from protection to disguise to performance, and are used in many different contexts, including medicine, theater, and sports.