A gas delivery mask apparatus is provided. The mask apparatus may include a mask body, a face mask, and a bellows. The mask body may include a tube configured to extend upwardly adjacent a subject's forehead. The face mask may be configured to deliver gas to the subject and may include a flexible cushion portion configured to interface with the subject's face and a substantially rigid base portion configured to support the cushion portion. The bellows may be configured to couple the tube with the substantially rigid base portion of the face mask. The bellows may be flexible to allow movement of the face mask relative to the tube.