iSpring FA15 Water Filter, Clear Includes high-quality 3-layer Alkaline mineralization filter cartridge with Mineral Stone, Calcite, and Corosex Uses FDA grade material and media, tested by independent third-party to meet NSF/ANSI Standard Improves the taste of RO water by adding back minerals such as ionized calcium, magnesium, sodium, and potassium ions Increases the pH level by 0.5-1.2, which helps minimize the fluctuations of your body's pH Provides better hydration than plain water