Nasal cannula assemblies and related parts

A nasal cannula assembly for administering a breathable gas to a user, the nasal cannula assembly comprising:

• a first section formed from a first material;
• a second section formed from a second material;
• a manifold with a manifold connection comprised of a rigid material relative to the first material;
• wherein the first section is relatively softer than the second section, wherein the first section and the second section comprises a body defining an open cavity engageable by the manifold connection, the first section defining at least in part said open cavity;
• a rear portion of said body being, in-use, substantially adjacent to the user's septum region, the rear portion being substantially compliant or deformable in response to a pressure applied by the user to said rear portion, wherein the rear portion defines at least a part of a rear wall of the open cavity, formed as a pillow section to be substantially adjacent to the user's septum region in-use, the rear portion being one or more of:
• a substantially thinned wall section of the body, or a substantially elasticised wall section of the body;
• wherein the manifold connection is substantially C or U shaped and a concave rear side of the C or U shape, in use, faces the rear portion, wherein the body covers the concave rear side of the C or U shape and a front side of the manifold connection when the manifold connection is received within the body.

A nasal cannula assembly for administering a breathable gas to a user, the nasal cannula assembly comprising:

• a nasal cannula comprising:
• a first section comprising a first material, and
• a second section comprising a second material;
• a manifold with a manifold connection comprising a rigid material relative to the first material, wherein the manifold connection is substantially C or U shaped;
• wherein the nasal cannula comprises a body defining an open cavity configured to receive the manifold connection for delivery of the gas to the user, the first section defining at least a portion of the open cavity, wherein the manifold connection is substantially C or U shaped and a concave rear side of the C or U shape, in use, faces the rear portion, wherein the body covers the manifold connection from the concave rear side to a front side;
• wherein a hollowed region is bound by the substantially C or U shaped manifold connection and a rear portion of the body when the substantially C or U shaped manifold connection is received within the body, the hollowed region substantially adjacent to the user's septum region in-use, the rear portion configured to deform the hollowed region to improve comfort or reduce the application of pressure points by the substantially C or U shaped manifold connection.