Devices comprising a plug positioned within a housing to regulate air within a container, for example, plastic storage containers or bags. One embodiment utilizes a plug that occludes an opening in a housing. The plug is displaced from the opening to inject or evacuate air from a container. An alternative embodiment utilizes a plug having air channels therein which can be sealed once air has been injected into or evacuated from a container. The devices are utilized with hose adaptors connected to vacuum or air hoses having specialized hose tips for coupling with the housing.