This complete line of liquid diaphragm pumps is designed to maximize efficiency, compatibility and economy in many applications. Pumps are engineered for low-pressure applications and can handle even the most abrasive or shear-sensitive materials. These self-priming pumps run at variable flow rates controlled by air pressure or fluid back pressure regulation, and are available with a variety of accessories. An unbalanced air valve design eliminates valve centering and pump stall-out, even under low air inlet pressure.