An infant nasal interface mask for use with a nasal continuous positive airwaypressure (nCPAP) system including a mask body and a base. The mask body forms acavity and is defined by a leading portion, an intermediate shell portion, anda trailing portion. The leading portion terminates in a leading edge formingan aperture open to the cavity and having a generally triangular shape for placementover a patient's nose. The trailing portion includes a bellows segmentcharacterized by an increased flexibility as compared to a flexibility of theintermediate shell portion. The base extends from the trailing portion oppositethe leading portion and forms at least one longitudinal passage extending througha thickness of the base and fluidly connected to the cavity. The intermediateshell portion is laterally pivotable relative to the base via the bellows segment.
