Update your hydraulic system to be Ready for the Road Ahead , with the Williams Controls 1/8" NPT WM219C4 Series 3-Way 2-Position Toggle Valve. This replacement part effectively controls the internal air pressure buildup of valves, fifth wheels, cylinders, and PTOs. Fashioned for panel mounting with a 2-way two position alternating valve for idle and active machinery. FleetPride is your First Click in Heavy Duty .