There is disclosed a drinking receptacle comprising: a container for containing a fluid for drinking； and an outlet member having an outlet through which the fluid is delivered under a pressure supplied by a user of the receptacle and a collar portion that attaches to an opening of the container such that an undersurface of the collar portion abuts with an upper surface of the opening of the container to form a substantially sealed engagement between the outlet member and the container； wherein either the undersurface of the collar portion or the upper surface of the opening of the container has at least one vent formed therein, the at least one vent being configured such that when said pressure is applied to the outlet member the at least one vent member permits the controlled ingress of air into the container to facilitate flow of fluid from the outlet, and when said pressure is removed the at least one vent member substantially prevents the ingress of air into the container to facilitate a controlled vacuum pressure within the container.
