The IRV valve provides in one compact insert cartridge the typical function of shock relief valve, side-in nose-exhaust. When the pressure at the high pressure inlet (2) reaches the valve setting, the valve starts to open to tank (1). The pressure rise is very low thanks to the smart deflector design. Flow passage in the opposite direction (1 to 2) is blocked. High precision machining guarantees quick response to load changes, limited hysteresis and reduced internal leakage.