The regulator comprises at least a cylinder (2) with a fluid inlet connector (1) for receiving fluid at an inlet pressure and a fluid outlet connector (4) for delivering fluid, at least one chamber (3), a rod (5) in said cylinder with one side submitted to the inlet pressure and the other side submitted to the outlet pressure generating a net force counter-balanced by at least one spring means (7) acting on one side of said rod (5) against said inlet pressure, wherein a fluidic pathway is formed between said rod (5) and said cylinder (2) as the major fluidic resistance of the device, wherein a change of the inlet pressure induces a move of the rod along the axis of the cylinder thereby modifying the fluidic resistance of said fluidic pathway, wherein the fluidic resistance of said pathway varies with the applied pressure at the inlet in a predefined range of pressure, inducing a regulated flow rate in the considered range of pressure.