Cistern flushed urinals are the most commonly used in the UK. There are two main installation types; exposed and concealed. In an exposed installation the cistern is wall mounted externally whereas in a concealed installation the cistern would be hidden behind the wall. The sparge pipes connecting the urinals to the cisterns would generally also be concealed or exposed accordingly. Spreaders, fitted on the urinal, connected to the flush pipes, spread the flow of water to both sides of the urinal.