This 13mm flow control valve is designed for regulating flow within a 13mm supply hose. Key Benefits Include: Made from black UV stable material - quality feel and unrivalled performance Controls the flow of water along a 13mm supply hose to ensure water efficiency High quality 13mm flow control valve. Shuts off or adjusts the flow in the 13mm supply hose. Simply turn the valve to open and close the water supply. Made from UV stable plastic. Category - Automatic Watering.