For regulating or shuting off the water flow at one end of the Y-coupling The GARDENA Control Valve gives you more flexibility when using a Y-coupling (sold separately). Connect the valve to one of the two outlets of the Y-coupling and you are ready to fully adjust the water flow or even shut it off completely. When the water flow is stopped, you can change the connection device on the spot without having to turn off the water at the tap first. The regulating valve is ideally suited for use with a sprinkler, as you can conveniently adjust the spray range by regulating the water flow. The adapter can be used all year round due to its frost resistance. The Control Valve is a real made-in-Europe quality product and GARDENA offers a warranty of five years on the Control Valve. Das Original GARDENA System