Membrane S1227RS = 25 GPD TFC Revised Seal Membrane used in Microline TFC3,TFC4D and 25S since 1994.
This is original manufacturer membrane.
Note: This is a common Microline / Clack Corporation 11 1/2" length from tip to tip, replacement membrane.
The new S1227RS membrane now can produce up to 35 gpd.
Can be used in all 25 gpd systems and the newer 35 gpd Microline Reverse Osmosis systems.
Or as a replacement for the S1224RS, CTA Membrane ( requires using S7028 as pre-filter ).