The HydroWorks toilet fill valve solves the two biggest reasons for water loss in toilets: miscalibration and leaks. Engineered by a fourth generation plumber, this toilet water fill valve saves up to 5 quarts per flush. The patented mini-valve on this toilet water fill valve calibrates the amount of water being send to the bowl during the tank refilling process. HydroWorks Toilet Fill Valve also detects leaks and sends out a signal. You can easily install this toilet water fill valve without tools — and you don"t even have to remove the tank. The Patented Smart Nut click when hand-tight to avoid leaks or cracks that can be caused by over-tightening. Float Lock shuts water off inside the tank for in-tank repairs. HydroWorks Toilet Fill Valve: * Incredibly economical * Engineered by a fourth generation plumber to save water * Patented Mini-Valve calibrates the amount of water being sent to the bowl during the tank refilling process * Saves up to 5 quarts per flush * Also detects leaks and signals when a leak is found