* 225, 5th stage Inline Alkaline filter with clear housing * Replacement filter for the RO6-ALK 6-stage RO/ Alkaline water system. * Add Calcium and Magnesium minerals back to the water after RO process, so the pH level can be raised from 7 to about 9.0 to 10.5 * Recommended to replace once a year * Dimension: 2” x 10”