Abstract: A closure for a container incorporating an air valve to facilitate inflation of a bladder within the container. The closure includes a plug for sealing an opening with the container lid. The plug has a central aperture within which is seated a valve adapter. Extending through the aperture and engaging the valve adapter is a valve stem fluidly connected to an inflatable bladder. The valve adapter maintains the valve stem above the closure for connection to an air supply for inflation of the bladder. A cap snap-fits over the adapter and valve stem to protect the valve from contaminants and damage. The bladder is inflated after the container has been filled.