Headgear and a patient interface, or components of headgear or a patient interface, such as a nasal cannula are provided. In one embodiment is a size adjustable headstrap to be provided as a headgear or a part thereof, in another is a portion of a headstrap or component for association therewith in which the portion or component facilitates improved location of the strap upon a user's face, in another embodiment is a system for encapsulating or covering a connector from contact with a user's face or facial skin, in another embodiment is a face mount part or body for a patient interface of a particular configuration, and in yet a further embodiment is a gases flow manifold for delivering of gasses to a patient interface of a particular configuration for improved patient comfort.