1-Year Filter Replacement Kit for RainSoft 21179 Reverse Osmosis System (RO Membrane Sold Separately) INCLUDES: STAGE 1 - 1 x Carbon Block Pre Filter - Replace Every 6 - 12 Months STAGE 2 - NOT INCLUDED (RO Membrane Sold Separately) STAGE 3 - 1 x Carbon Block Post Filter - Replace Every 6 -12 Months (2) 5 micron carbon filters included with this kit only. Filters may need to be replaced more often than indicated depending on incoming water contaminant levels and volume of water being treated. -This is a non OEM replacement product This filter set includes: (x2) 5 Micron coconut shell carbon block filters, 10" x 2.5" inches CARBON BLOCK IPW Industries Inc carbon blocks are manufactured with a high purity Coconut Shell Activated Carbon. Our acid washed carbon blocks activate the carbon to make it more porous and able to remove more contaminants than standard water washed carbon. With a high chlorine reduction, great dirt-holding capacity, and greatly reduced carbon fines, you will soon make our Carbon Blocks your preferred choice! Additional Details ------------------------------ Product description: 1-Year Filter Replacement Kit for RainSoft 21179 Reverse Osmosis System (RO Membrane Sold Separately) INCLUDES: STAGE 1 - 1 x Carbon Block Pre Filter - Replace Every 6 - 12 Months STAGE 2 - NOT INCLUDED (RO Membrane Sold Separately) STAGE 3 - 1 x Carbon Block Post Filter - Replace Every 6 -12 Months (2) 5 micron carbon filters included with this kit only. Filters may need to be replaced more often than indicated depending on incoming water contaminant levels and volume of water being treated. -This is a non OEM replacement product This filter set includes: (x2) 5 Micron coconut shell carbon block filters, 10" x 2.5" inches CARBON BLOCK IPW Industries Inc carbon blocks are manufactured with a high purity Coconut Shell Activated Carbon. Our acid washed carbon blocks activate the carbon to make it more porous and able to remove more contaminants than standard water washed carbon. With a high chlorine reduction, great dirt-holding capacity, and greatly reduced carbon fines, you will soon make our Carbon Blocks your preferred choice!