Corrosion resistant material. Alerts you to water waste, automatically signals if tank leak should develop. Fits most toilet tanks. Anti-siphon design prevents contamination of fresh water supply. Valve height and water level adjusts for correct fit and most efficient flush level. The Bulls Eye Flappers corrosion free plastic seat assures complete shut-off, no more handle jiggling. Simplified design eliminates old brackets, lift wires and assures positive alignment. Chlorine-resistant for harsh water regions. Meets anti-siphon codes. Carded.