The levelling valve is installed as a level control valve for load depended height control using the air bellows of vehicles with air suspension. Depending on the version, additional functions are possible.
- Versions with a zero point adjustment (Port No. 4) provide a 2nd ride height. This can be useful in case a lift axle is up and you need more clearence to the ground.
- Version with height limitation restricts, together with a Raise/Lower valve (COLAS), the lifting action when a maximum permissible body height is reached.