Abstract: An inflater sealer machine is disclosed which clamps the open upper portions of a flexible container, fills the package with a quantity of gas, and subsequently seals the upper container portions closed. The clamping means of the machine comprises a pair of clamping members capable of moving together to hold the upper portions of the container together. The inflating means includes a tube which extends through the clamping members into the open upper container portions. The sealing means comprises a pair of sealing members adjacent to the clamping members and capable of moving together to seal together the upper portions of the container while the container is inflated. A pneumatic control system, including a "piggy-back" pneumatic cylinder, is also disclosed for controlling the sequential actions of the clamping, inflating, and sealing means.