Adjustable water height toilet fill valve Anti-Siphon Tower Fill Valve ; Water Saver ; Universal fit for both 1 and 2 piece toilets Adjustable 7 to14 in. High fits short & tall Tanks Fill Valve Fits all American type Toilets. NuFlush Adjustable Water Height Fill Valve. Fill Valves are designed to fill the toilet tank with water from the water supply line after it has been emptied by a flush. This fill valve is a universal fit for 1 and 2 piece toilets that are bottom water fed with a 7/8" pipe connection. The fill valve replaces the ballcock mechanism and is more efficient and easy to install.