A vent prevents a vacuum from forming within an inverted container of liquid when the liquid is dispensed. The vent is a singular vent, formed of a vent tube, the vent tube removably secures with a nipple, and more particularly its radially extending flange, with the nipple flange having a passage therethrough to allow for venting by way of the vent tube from the interior of the container to the location between the container neck and its collar, to provide for the entrance of atmospheric air into the interior of the container during usage to prevent the generation of any vacuum therein. The container may be a nursing bottle, with its collar and nipple applied to the top, and the vent tube being secured to the bottom of the nipple flange for projecting downwardly within the bottle to perform its venting function. The bottle may be formed of fully or partially transparent material, tinted to one or more coloration, while the vent tube may be tinted to one or more different coloration, and when they are assembled, exhibits three or more colorations for the vent tube when viewed from exteriorly of the tinted nursing bottle during its application.
