The AK-Series, family of proprietary thin-film reverse osmosis membrane elements are characterized by high flux and excellent sodium chloride rejection. AK Low Pressure Brackish Water Elements are selected when high rejection and low operating pressures are desired. These elements allow significant energy savings since good rejection is achieved at operating pressures as low as 100 psig (689 kPa). AK8040F 400 Low Pressure Brackish Water elements feature a FRP outer wrap and 27 mil feed spacers. This element is designed with flush end connections.