ScaleRX protects your water heater from limescale build-up and keeps it running efficiently. It requires no power supply, batteries, chemicals, or filters. ScaleRX uses a patented Turbulent Galvanic Polarization (TGP) system to disrupt the formation of limescale crystals on water heater elements. In side-by-side comparison testing, ScaleRX was four times more effective than the leading electronic scale device. ScaleRX is easy to install and maintenance free. Now available in 3/4 inch & 1 inch sizes