4.5 gpm Max Flow Diaphragm Pump 3 x 1/2" Quick connect fittings provided (1 straight barb, 1 1/2" NPT, 1 elbow barb) Includes Protective Strainer (For use in water applications only, for backup protection only) This pump is an on-demand water delivery pump. The original design is for supplying water to a faucet or shower head. When pressure builds to 40 psi, the pump will shut off until pressure is relieved. This pump has been fitted with viton orings so that it is now compatible with biodiesel. Although originally designed for water pumping, The pump can run dry without damage. Pumps on Demand when below 40 psi Continuous Duty Cycle Sensor shuts off pump at 80°C (176°F) Pump turns off automatically when 40 psi has been achieved. Max vacuum pressure ~10mm Hg *Max Suction Height Between 0.5 - 1.0 Meters (1.5 - 3.5 ft) This pump can draw fluids through the suction side of a hose without priming. Biodiesel Applications: This pump is a very useful tool in dry wash resin towers. Simply plumb the pump in to the tower so that it pushes the biodiesel into the bottom of the tower and out the top. Use a ball valve at the outlet of the tower to restrict flow. The pump will build up to 40 psi and then shut off. It will turn back on as pressure is relieved from the slow flowing biodiesel exiting the tower. This allows full control of the flow rate through the tower so adequate flow rates can be achieved. This pump can be left on over-night and does not require any attendance once the proper valve opening has been set.