This invention relates to connectors to be provided into fluid communication or engagement either directly with, or via a component to be associated with, a terminal end of a breathing conduit. In at least one embodiment, the connector comprises a body having a first end and a second end, and an internal lumen for the passage of gas between the ends. The first end engageable with a terminal end of a conduit or a component to be associated therewith. The second end engageable with another connector. An internal surface of the body at the second end comprises internal connection features for connection with another connector to be received internally therein. An external surface of the body comprises one or more external alignment feature(s) for aligning the connector or another connection into an aligned orientation for connection therebetween.