Pressure Regulator MS4-Lr-1/4-D5-As 4 bar Maximum Output Pressure, with Pressure Gauge, Lockable Regulator Head, Direction of Flow: From Left to Right. Size=4, Series=MS, Actuator Lock=(* Rotary Knob with Lock, * with Accessories, Lockable), Assembly Position=Any, Design Structure=Directly-Controlled Diaphragm Regulator, Festo