A mask seal assembly (40, 540, 640, 740) for use as part of an apparatus for supplying a flow of respiratory gases to a user, the mask seal assembly (40, 540, 640, 740) comprising: a seal (43, 543, 643, 743) of flexible material, and a clip (42, 542, 642, 742) of rigid material, the seal (43, 543, 643, 743) having a first side (5431, 6431, 7431) and a second side (5432, 6432, 7432), the first side (5431, 6431, 7431) of the seal (43, 543, 643, 743) being shaped to approximately match contours of the user's face and in use substantially seal against the user's face, the second side (5432, 6432, 7432) attached to said clip (42, 542, 642, 742), the clip (42, 542, 642, 742) providing an interface extending substantially the full perimeter or periphery of the mask seal assembly (40, 540, 640, 740), the clip (42, 542, 642, 742) having a first side and a second side, the second side (5432, 6432, 7432) of the seal (43, 543, 643, 743) being attached to the first side of the clip (42, 542, 642, 742), and the second side of the clip (42, 542, 642, 742) for releasably attaching the mask seal assembly (40, 540, 640, 740) to a mask body, characterised in that: the clip (42, 542, 642, 742) comprises a bridging portion (50, 650, 750) spanning between the first side and the second side of the clip (42, 542, 642, 742) to space at least a portion of the second side (5432, 6432, 7432) of the seal (43, 543, 643, 743) outwards from a perimeter or periphery of the second side of the clip (42, 542, 642, 742), the mask seal assembly (40, 540, 640, 740) comprises a second seal of flexible material attached to the second side of the clip (42, 542, 642, 742) for forming a seal between the mask seal assembly (40, 540, 640, 740) and the mask body, and the seal (43, 543, 643, 743) and the second seal are integrally formed and joined together across the bridging portion (50, 650, 750) via a runner across or through the bridging portion (50, 650, 750). a seal (43, 543, 643, 743) of flexible material, and a clip (42, 542, 642, 742) of rigid material, the seal (43, 543, 643, 743) having a first side (5431, 6431, 7431) and a second side (5432, 6432, 7432), the first side (5431, 6431, 7431) of the seal (43, 543, 643, 743) being shaped to approximately match contours of the user's face and in use substantially seal against the user's face, the second side (5432, 6432, 7432) attached to said clip (42, 542, 642, 742), the clip (42, 542, 642, 742) providing an interface extending substantially the full perimeter or periphery of the mask seal assembly (40, 540, 640, 740), the clip (42, 542, 642, 742) having a first side and a second side, the second side (5432, 6432, 7432) of the seal (43, 543, 643, 743) being attached to the first side of the clip (42, 542, 642, 742), and the second side of the clip (42, 542, 642, 742) for releasably attaching the mask seal assembly (40, 540, 640, 740) to a mask body, characterised in that: the clip (42, 542, 642, 742) comprises a bridging portion (50, 650, 750) spanning between the first side and the second side of the clip (42, 542, 642, 742) to space at least a portion of the second side (5432, 6432, 7432) of the seal (43, 543, 643, 743) outwards from a perimeter or periphery of the second side of the clip (42, 542, 642, 742), the mask seal assembly (40, 540, 640, 740) comprises a second seal of flexible material attached to the second side of the clip (42, 542, 642, 742) for forming a seal between the mask seal assembly (40, 540, 640, 740) and the mask body, and the seal (43, 543, 643, 743) and the second seal are integrally formed and joined together across the bridging portion (50, 650, 750) via a runner across or through the bridging portion (50, 650, 750). the clip (42, 542, 642, 742) comprises a bridging portion (50, 650, 750) spanning between the first side and the second side of the clip (42, 542, 642, 742) to space at least a portion of the second side (5432, 6432, 7432) of the seal (43, 543, 643, 743) outwards from a perimeter or periphery of the second side of the clip (42, 542, 642, 742), the mask seal assembly (40, 540, 640, 740) comprises a second seal of flexible material attached to the second side of the clip (42, 542, 642, 742) for forming a seal between the mask seal assembly (40, 540, 640, 740) and the mask body, and the seal (43, 543, 643, 743) and the second seal are integrally formed and joined together across the bridging portion (50, 650, 750) via a runner across or through the bridging portion (50, 650, 750).