Abstract: A mask for directing air to the facial area of a patient includes a mask body in the form of a conduit, a seal connected to an outlet end of the mask body for contacting the patient's face in a sealing relationship, the seal being soft and pliable for patient comfort, and a vent tube connected to an inlet end of the mask body to supply air to the mask body. The mask body is relatively flexible compared with the vent tube so that lateral stresses on the mask body are initially accommodated by distortion of the mask body rather than on breaking the sealing relationship between the seal and the patient's face. A frame is mounted for movement along the mask body to press the seal against the patient's face. The frame includes a nose bridge portion, an upper jaw portion, and two lateral portions, and the two lateral portions of the frame are contoured to conform to the shape of the seal so that gentle contact between the frame and the seal causes only the two lateral portions of the frame to touch the seal.