This is an Excellent Replacement Filter Pack For Your RO System . Nexus Filters are Very High Quality and do a Very Good Job Producing Clean good Water For any Residence . 5 Micron Sediment Filter : With Only Five Micron Rating . It is effective in Removing Dirt , Rust , Sand Particles etc. Carbon Filter : It Takes out of the Chlorine and Organic Chemicals It Provide Enhanced reduction of Taste , Odour Color etc, Post Carbon Filter : This Carbon Post Filter Removes objectionable taste and odour to enhance the Quality of Your Drinking Water We are Using Coconut Carbon & Mineral in Post Carbon to Guarantee the Taste of Water.