Fluidmaster Pro Compact Syphon 8" can be used in a toilet cistern or a cold water storage tank. The cistern does not have to be fitted to an external wall, making it ideal for a closet WC or a WC located in the middle of a building. It features an internal overflow that will cope with at least 30 litres/min. The dual flush allows for a full or partial flush to save water. The syphon is a leak free component providing the back-nut is tightened sufficiently.