1-Year Replacement Filter Kit for RainSoft UF22 Reverse Osmosis System (RO Membrane Sold Separately) 1-Year Replacement Filter Kit for RainSoft 21179 Reverse Osmosis System (RO Membrane Sold Separately) - 1-Year Replacement Filter Kit for RainSoft UF22 Reverse Osmosis System (RO Membrane Sold Separately)