One-Way Flow Control Valve Grla-1/8-QS-4-Rs-D with Knurled Screw and Lock Nut Valve Function=One-Way Flow Control Function for Exhaust Air, Pneumatic Connection, Port 1=Qs-4, Pneumatic Connection, Port 2=G1/8, Adjusting Element=Knurled Screw, Mounting Type=Threaded, Festo