Nasal mask and system using same

A nasal mask assembly that includes a seal member defined from a unitary piece of elastomeric material. The seal member defines a nose receiving cavity and has a first end portion and a second end portion generally opposite the first end portion. A first opening in the first end portion allows at least a portion of a nose to enter the nose receiving cavity such that the nares of the patient communicate with the nose receiving cavity. The seal member includes a neck portion defined in the second end portion and a second opening defined in the neck portion in communication with the nose receiving cavity. A reinforcement area is provided on the side walls of the seal member. The reinforcement area comprises a saddle shaped contoured area on each side of the seal member. Each saddle shaped area has an upper and a lower protrusion portion for providing supporting contact with the face.