Abstract: This air operated plastic pail capper machine is designed to quickly and effectively push a cover onto a pail, while also pushing out any air that may be above the contents of the pail. Primarily, it consists of a base with rollers on top for easy alignment of a pail with a plate attached to a piston rod of an air cylinder, and the air cylinder is mounted to a sleeve attached to a post secured to the base of the machine. Palm operated valves are also employed to operate the machine.