An inflatable face seal (1′ 30′) for a respiratory mask, the inflatable face seal comprising an annular air-tight hollow portion (12′ 40′) where a cross section through one section of the annular hollow portion (12 40) comprises a bonded joint (11 41) which joins two overlapping flanges (6,7 35,36). The two flanges are bonded together such that an inwardly facing surface (10 39) of a first flange (6 35) of the two overlapping flanges is in contact with an outwardly facing surface (9 38) of a second flange (7 36) of the two overlapping flanges. In this way, the bond is strong and only exposed to shear stresses when the annular air-tight hollow portion is exposed to increased pressure.
