The Premium 10 Stage Filter contains the premier, patented, 10-Stage contaminant removing filter. It lasts three times as long as the common carbon block filters (1500 gallons versus 500 gallons). It filters contaminants by bonding the contaminants with the media inside the filter. The Premium 10 Stage Filter removes or greatly reduces the following: chlorine, cancer causing organic/chlorine compounds called trihalomethanes (THM), bad odors, e.g., hydrogen sulfide which gives water a rotten egg smell, pesticides, herbicides, PCB's, toxic heavy metals i.e., lead, cadmium, organic arsenic, asbestos, micro-organisms (protozoa and cysts) such as cryptosporidium and giardia, and dozens of other lesser known organic contaminants.