Patent ID: 7861715

Claim:
A mask system for treating sleep disordered breathing, comprising: a flexible shell and cushion unit including a cushion portion forming a seal with a patient in use, and including a shell portion, the shell portion including at least one frame-receiving channel defined by a front surface and a rear surface, and an aperture centrally located on the shell portion, the flexible shell and cushion unit being an integral single piece of silicone defining an interior breathing chamber; a rigid frame including at least one frame edge shaped to fit into and be secured within the at least one frame-receiving channel with the at least one frame edge engaging the front and rear surfaces of the frame-receiving channel, the frame supporting the shell and cushion unit in use, the frame including a plurality of projecting frame ribs received within a portion of the flexible shell and cushion unit, the frame having a first side portion and a second side portion; a rigid ring-shaped member including a rear end positioned at least partially within the aperture of the shell portion to communicate with the interior of the breathing chamber, the ring-shaped member including an annular front flange, the rear end having an outer circumferential surface that engages with an inner circumferential surface defined by a wall of the aperture; a rotatable elbow having a first end and a second end, the first end including a groove or recess provided to and engaging with the annular front flange of the ring-shaped member; a swivel provided to the second end of the rotatable elbow, the swivel including a first end adapted to engage with the elbow, and the swivel having a second end adapted to engage an air delivery conduit; a plurality of vent holes provided in the shell portion; four headgear attachment points formed on the frame, a first pair of the four headgear attachment points being provided on the first side portion of the frame, and a second pair of the four headgear attachment points being provided on the second side portion of the frame; and four-point headgear attached to the four headgear attachment points in use, the four-point headgear including strap end portions being adapted to be threaded through one or more slots associated with the headgear attachment points, wherein the mask system does not have a forehead support.