The MARLO MRO-4-LP Series Commercial Reverse Osmosis system offers a low pressure, energy saving design for light commercial water purification applications requiring an economical means for high purity water. Nominal output capacities of 3,600 – 16,200 GPD. These units come standard with a solid-state digital controller and automatic inlet shut-off valve among many other standard and optional features.Low pressure, energy saving design for light commercial water treatment applications requiring an economical means for high purity water. Nominal output capacities of 3,600 – 16,200 GPD.