Interfaces for positive pressure therapy having a mask assembly, a headgear assembly and a connection port assembly are disclosed herein. The connection port assembly has a ball joint connection with the mask assembly and includes a quick release button for easily disconnecting the gases source conduit from the mask assembly. The mask assembly may include a bias flow vent that is formed separately and attached to the mask assembly. The headgear assembly encircles the rear region of the user's head and may include at least some portions that are substantially non-stretchable.