Concealed shower systems are also mixer showers that use both hot and cold water supply and all the workings are on the inside of the wall. They are mostly thermostatic (which means that the temperature is constantly regulated & controlled in case of any interruptions to the hot or cold water supply). Manual showers are the opposite and don’t have a constant temperature control.
They are favourable for stud walls or require false walls due to the main body of the valve which fits into the wall. Spare part cartridges are easily accessed by removing the front knob for maintenance. An advantage of this valve is that it can be placed in a different location to the shower heads meaning you can turn the shower on without getting your hand wet.
You can have a massive selection of different combinations of single handset on a clip or a slider rail or a large drench head above as well body jets and even bath fillers. Mainly available in 1 , 2 or 3 functions.