Abstract: A stacked water injection regulator for controlling liquid flow into a subterranean formation having a bore hole therein, including having a mandrel having a single side pocket, a multiplicity of longitudinally aligned and physically connected liquid flow regulators and a single latching means for securing regulators in the pocket. The mandrel and the regulators together form at least two axially opposite flow paths from the interior of the bore hole to common injection ports at the exterior of the mandrel in fluid communication with the subterranean formation.