The HC550 HydroClean Toilet Fill Valve saves water and detects leaks. It Installs quickly and easily without tools, eliminating guesswork. The easy calibration assures a full flush power. It is designed for areas of the country where the water supply is free of iron, bacteria, sediment and other particulate matter and does not need the Tank Cleaning Turbo Jet technology offered with the HydroClean HC660 model.Water-saving toilet fill valve with built-in mini-valve that adjusts tank refill water levelCalibrates to adjust the exact amount of water needed to help save on water usageMini valve to control amount of water going back into the bowlCleans tank by removing rust and sedimentShuts off water inside tank making repairs a snapRefills quickly: height adjusts from 11 in. - 13.8 in.