Conventional expansion tanks require separate mounting, high pressure charge air that may not be available at start-up, regular pressure checks and continuous charging to maintain a desired pressure level in the expansion tank air chamber. In addition, some require manual adjustment of the pressure in the air chamber when the target pressure of the material changes. Graco's active pressure equalization tank is integrated into the line to keep the pressure stable. It operates with normal compressed air, eliminating the need and additional cost for high pressure charge air. Thanks to the active air pressure equalization, there is no need for periodic air pressure checks. The automatic adjustment function eliminates the need for manual adjustment of the air pressure when the target pressure of the material changes. In addition, a safety seal prevents paint from leaking in the event of a diaphragm rupture.