Microline TFC-25S RO System Replacement Water Filter Kit S7028|S1227RS|S7025. Microline TFC-25S RO System Replacement Water Filter Kit provides a complete one year supply of filters for your TFC-25S reverse osmosis system. This kit includes all pre and post filters as well as the membrane. Kit includes: Qty. 1 – S7028 Compatible Sediment/Carbon Block Prefilter Qty. 1 – S1227RS TFC RO Membrane 25 gpd Qty. 1 – S7025 GAC Postfilter Note: Reverse osmosis membrane needs to be replaced every 2-3 years. Microline TFC-25S