These products are non-salt-based water conditioners designed to manage and inhibit the formation of hard water scale (limescale) without chemically removing the beneficial hardness minerals (calcium and magnesium) from the water. They typically use a physical process, such as Template-Assisted Crystallization (TAC), which changes the structure of the mineral ions, causing them to remain suspended in the water and pass through the system without adhering to pipes, fixtures, or heating elements. This solution is a preferred, low-maintenance, and eco-friendly alternative to traditional salt-based water softeners, particularly for protecting heat-exchange components like tankless water heaters.