water Diving mask and full face diving mask, watertight masks covering the mouth, nose and (in the latter case) eyes, allowing the wearer to breathe underwater from a self-contained or surface-supplied breathing gas supply Diving helmet, covering the entire head in a dome of air. By coverage Quarter-mask or orinasal mask, covering the mouth and nose only Half-mask (disambiguation), from below the eyes to below the chin Fullface mask, from above the eyes to below the chin