Clacks WS1.25 Automatic valve is a control head designed for residential and commercial applications. Its design and functioning is much the same as the WS1, but the larger innerworkings of the valve allow for flow rates up to 7.7 m³/hr.

The valve acts as a primary center that directs and regulates all cycles of water softening or filtration. It can be set to perform downflow/upflow regeneration or simply backwash and rinse.

The valve comes in different program versions and is controlled by a solid state microprocessor with front panel setting and screen display. The WS1.25 has 11 injector sizes to choose from for different draw rates.