Patent attributes
A mask assembly including a mask frame with a central conduit connection aperture and lateral arms having a 3-D curvature. The lateral arms extend: outwardly from a center of the frame, rearwardly, towards the patients ears, and upwardly, along a vector passing from below the nose to a point between the temple the top of the ear. The mask assembly can include an anti-rotation feature which limits or prevents rotation between straps of a headgear, and the mask frame. The mask assembly can include a buckle for a closed loop headgear, the buckle being formed with a plurality of openings and posts configured to form an angled headgear strap path through the buckle through which part of a headgear strap loop can pass.