The ARO 1½” EXP Metallic is a diaphragm pump that is 20 to 40 percent more efficient than its competitors. Its compact, durable design with the housing constructed of aluminum, cast iron, stainless steel, and hastelloy-C making it highly durable. It features a wide variety of matierials that maximizes its compatibility with ant fluid. It also ensures a no-stall operation as it is integrated with an "unbalanced"air valve. It has an air inlet pressure range of 20 - 120 p.s.i. with a maximum material inlet pressure of 10 p.s.i as well as having a fluid pressure range of 20-120 p.s.i. It has a maximum flow rate of 123 g.p.m and operates with minimal noise of 82.8 db at 70 p.s.i.