Water Factory 3M Compatible Filter Kit 3-stage - Membrane Not Included1 Year Filter Replacement Kit for CUNO Water Factory SQC3 Reverse Osmosis System or the Ionics GI1 or GI2 RO Systems (RO Membrane Sold Separately) INCLUDES: STAGE 1 1x Sediment Pre Filter (CSM5651) Replace Every 12 Months STAGE 2 0x (RO Membrane CSM5672 Sold Separately or with Replacement Kit YSM CSMSQC3) Replace Every 24 Months STAGE 3 1x Carbon Block Post Filter (CSM5621) Replace Every 12 Months *Filters may need to be replaced more often than