GE MRO-MB Merlin RO Membrane, Single Unit The Merlin System uses 2 membrane filters to provide exceptional TDS reduction (sold individually) Ultra fine reverse osmosis filtration provides great tasting drinking water and ice with outstanding clarity Merlin reverse osmosis membrane produces 748 gallons of purified water per day If you are storing this membrane for later use, be sure it's refrigerated and remember the shelf life is only 8 months