Concealed Thermostatic Shower Mixer Valve 1 / 2 Way Outlet Brushed Brass

  
A shower valve performs two basic functions, it controls the temperature and the flow of the water in your shower. It controls the temperature by mixing hot and cold water from your hot and cold-water supplies in different proportions and generally has a single control to do this with. It controls the flow by controlling the overall rate of flow of the water and directing that water to one or more outlets using flow controls and/or diverters. A flow control supplies water to a single outlet and can finely control the rate of flow from full off to full on. A 2-way diverter supplies water to two separate outlets by allowing switching between the two, only one can be on at a time.

Each outlet from the valve supplies water to each part of your shower that needs it. Shower valves usually have 1, or 2.

So, with a 1 outlet shower valve you could operate, for example, an overhead shower. With a two-outlet valve you could add, for example, a shower slide rail as well. Twin Shower Valves - One Way. Twin shower valves have two controls.

Twin one-way valves can supply a single shower function, for example an overhead shower or a small shower on a slide rail but not both. One of the two controls is a temperature control the other controls the rate of flow from full on to full off. Twin Shower Valves - Two Way. A twin two-way shower valve also has two controls.

Twin two way valves can supply two different shower functions but not at the same time, that is, it enables you to switch the water from one outlet to another, for example from the overhead shower to a smaller shower on a slide rail. The valve has a temperature control just like the twin one-way valve but instead it has a diverter which switches the water between one outlet and the other. The diverter can switch between shower functions, but it can't finely control the rate of flow, each outlet is either full on or full off.