A vent for venting exhaust gases from a component of a respiratory therapy system, the vent comprising: a substrate (15A, 115A) having an inner surface and an outer surface; and a plurality of vent holes (17, 117) arranged in a vent hole array extending through the substrate, each vent hole (17, 117) comprising an exhaust gas inlet (25, 125) at the inner surface of the substrate and an exhaust gas outlet (23, 123) at an outer surface of the substrate (15A, 115A), the exhaust gas inlet (25, 125) and the exhaust gas outlet (23, 123) each having a respective centre; wherein the exhaust gas inlet (25, 125) and the exhaust gas outlet (23, 123) define a draft direction being the direction that exhausted air flows out of each of the vent holes (17, 117) and which is defined by an axis that extends through the centre of the exhaust gas inlet (25, 125) and the centre of the exhaust gas outlet (23, 123) of each of the vent holes (17, 117); wherein the draft direction of at least some of the vent holes (17, 117) is not aligned with a draw direction, the draw direction, being the direction at which a mould tool is opened or removed relative to the vent during manufacture; wherein the vent holes (17, 117) have the same draw direction; at least one vent hole (17, 117) has a different draft direction from at least one other vent hole (17, 117); the vent hole(s) (17, 117) further from a centre of the vent have a draft direction which is inclined at a greater angle from the draw direction relative to the vent hole(s) (17, 117) nearer the centre of the vent; and the exhaust gas outlet (23, 123) of each vent hole (17, 17) has a larger diameter than the exhaust gas inlet (25, 125). a substrate (15A, 115A) having an inner surface and an outer surface; and a plurality of vent holes (17, 117) arranged in a vent hole array extending through the substrate, each vent hole (17, 117) comprising an exhaust gas inlet (25, 125) at the inner surface of the substrate and an exhaust gas outlet (23, 123) at an outer surface of the substrate (15A, 115A), the exhaust gas inlet (25, 125) and the exhaust gas outlet (23, 123) each having a respective centre; wherein the exhaust gas inlet (25, 125) and the exhaust gas outlet (23, 123) define a draft direction being the direction that exhausted air flows out of each of the vent holes (17, 117) and which is defined by an axis that extends through the centre of the exhaust gas inlet (25, 125) and the centre of the exhaust gas outlet (23, 123) of each of the vent holes (17, 117); wherein the draft direction of at least some of the vent holes (17, 117) is not aligned with a draw direction, the draw direction, being the direction at which a mould tool is opened or removed relative to the vent during manufacture; wherein the vent holes (17, 117) have the same draw direction; at least one vent hole (17, 117) has a different draft direction from at least one other vent hole (17, 117); the vent hole(s) (17, 117) further from a centre of the vent have a draft direction which is inclined at a greater angle from the draw direction relative to the vent hole(s) (17, 117) nearer the centre of the vent; and the exhaust gas outlet (23, 123) of each vent hole (17, 17) has a larger diameter than the exhaust gas inlet (25, 125).