This is the 12-volt solenoid that controls the air supply to your ARB Air Locker. It's a critical component in the system, typically mounted in the engine bay. When you hit the diff lock switch, this solenoid opens to allow compressed air to flow to your differential, engaging the locker. If your diff lock fails to engage, and you can hear the compressor running, a faulty solenoid is a very common cause. A failed solenoid means no locked diff, leaving you without that essential traction when you're in a tough spot off-road.
This solenoid is designed for ARB Air Locker systems installed in the listed vehicles. It is not a standard vehicle component. Please check your existing ARB system to confirm compatibility.