The present invention relates to a patient interface (240) for delivering breathable gas to a patient. The patient interface (240) comprises a mask (242) having a sealing portion (244) adapted to form a seal with the patient's nares. The sealing portion (244) has a supporting wall defining an air path and is structured to extend or curve outwardly from a supporting wall defining an air path. The patient interface further comprises headgear (245) adapted to secure the mask (242) to a head of the patient； a first alignment (250) indicator provided to the mask (242)； and a second alignment indicator (252) provided to the headgear (245). The first and second alignment indicators (250, 252) are positioned to align with each other only when the headgear (245) is connected to the mask (242) with a correct alignment.
