Aquasana Replacement Remineralizer  for Aquasana OptimH20 Reverse Osmosis  Water Filter Genuine replacement Remineralizer for Aquasana OptimH20 Reverse Osmosis Water Filter: AQ-RO-3 Use only genuine Aquasana replacements - untested replacements are not certified for performance capacity or contaminant removal Replacements made easy - no tools or plumber required - replace membrane every 12 months Removes over 95% of fluoride PLUS up to 99% of 87 other contaminants like lead, mercury, asbestos, and more Retains the healthy minerals like calcium, potassium, and magnesium for the healthiest water