The 3-way electromagnetic water valve also known as a solenoid valve will control the flow of water to 3 different shower features. Typically, a solenoid valve will be used as a switch to control the water flow to shower or steam shower features such as the overhead rainfall shower, body massage jets or foot massage.Depending on the shower these features can be controlled by a water diverter valve or through the digital control panel using such a solenoid. If you have a water feature that is control panel operated and this feature is no longer functioning then it could be the solenoid or electromagnetic valve that has failed. This is a 3-way valve and will control 3 different features. Please note that a sequence of body jets may be controlled together with one valve or separately using multiple valves. In some cases just one of the 3 valves may have failed.The input electrical supply for this part is DC 12V with each valve having 2 connectors.The width of the water connector is approximately 26mm or 1.02 inches. We have a reducer connector which screws onto the end of this which reduces the connection to 20mm or 0.8 inches. You can purchase the reducer here.Suitable for Aqualux and other brand name shower enclosures.