Scale Doctor is a compact, computerized electronic water conditioner, which will descale your existing system, prevent new scale from forming and save you money from the moment it is installed. How does it work? The principle of magnetic water treatment is not new. The first patent was granted around 1900. Scale Doctor takes this knowledge into the 21st century by using a patented technology. The electronic device treats the water by inducing magnetic AND electric fields with a continuous changing frequency within an optimized frequency band. This will affect the initial stage of crystal growth in the bulk of the water, resulting in many smaller crystals with a roundish shape, which will not easily adhere to pipe walls or other surfaces such as heating elements of washing machines and dish washers. As no new scale layers are being formed the force of the flowing water will slowly remove old scale layers, temporarily increasing hardness until all scale layers have been removed. The Scale Doctor is guaranteed for 10 years. If there are any issues, contact us and well send you a free replacement. All you pay for is the shipping.