Clack's WS1 Automatic valve is a control head designed for residential and commercial applications requiring flow rates up to 6.1 m³/hr. It has a backwash ability capable of servicing up to 21" diameter tanks.

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 has 11 injector sizes to choose from for different draw rates.