Air operated double diaphragm pumps for dosing and transferring a wide variety of fluids. This pump is good for CIPs chlorinated cleaning agents and home industrial cleaning agents. For OEM applications and industrial processes with lower flow rates. Unbalanced spool valve air motor requires lower start-up pressure for finer flow adjustment using regulating air pressure. Pump wetted materials are compatible with the most aggressive fluids and are suitable for use in corrosive environments. Air motor (directional air valve and air chamber covers) is made of polypropylene.