Filters sediment, algae, red worms and other impurities to double protect washing machines, smart toilets, and other appliances. Problem it solves: When water quality is poor and contains sediment or particles, heating cold water in the water heater can lead to scale and blockages over time. This can damage the water heater and affect shower performance. How it works: The prefilter is installed on the coldwater inlet to the water heater. It filters and purifies incoming water to protect the water heater and connected appliances. Compatibility and installation: Designed for the coldwater supply of the water heater. It helps protect appliances fed from the same supply, such as washing machines and smart toilets. Performance and benefits: Reduces sediment, algae and other impurities in the coldwater line, helping to prevent scale buildup, extend waterheater life, and maintain consistent hot water and shower quality. Use scenarios: 1) A home with sedimentrich or hard water uses the prefilter to prevent scale in the water heater, prolonging its life and maintaining heat output. 2) Homes with multiple appliances (washing machine, smart toilet) share the coldwater supply and benefit from added protection against impurities. 3) In scenarios with unclear or fluctuating water quality, the prefilter purifies incoming water before heating to improve reliability of hot water. Notes: Size and material information are not provided in the description. The product is a prefilter installed on the coldwater inlet to filter and purify water and protect the water heater.