The Aqua-Pure AP430SS Scale Inhibition System helps extend the life of appliances that use hot water (e.g., water heaters - standard and tankless and washing and dishwashing machines), as well as plumbing fixtures (e.g., faucets, pipes and shower heads). Offers a controlled dosage of polyphosphates for maximum system performance and cartridge life (avg. cartridge life is 4-6 months). Color: White.