Abstract: According to the invention, a single structure is provided to both produce pressure in and evacuate a space. The inventive device has a barrel with a chamber and separate vacuum and pressure passageways in communication with the chamber. A check valve is mounted in the vacuum passageway to permit flow of air into the chamber through the vacuum passageway but to prohibit flow out of the chamber through the vacuum passageway. A second check valve is mounted in the pressure passageway to permit flow of air out of the chamber through the pressure passageway but to prohibit passage of air through the passageway into the chamber. A plunger is movably mounted in the chamber to selectively develop pressure in the chamber and pressure passageway upon being moved in a first direction and to draw air from the chamber and evacuate the vacuum passageway upon being moved opposite to the first direction.