This four stage Kwik-Change reverse osmosis is equipped with a unique swivel valve in head, Kwik-Change assembly. This allows for a simple and sanitary filter change that does not require you to turn off the water source to the system. Stage 1 is a five micron sediment filter that traps particulate matter like dirt, rust, sand silt and sediment. Stage 2 is a five micron carbon block filter that provides a reduction of chlorine, chloramines and other materials that cause bad taste and odors. Stage 3 is the reverse osmosis system membrane. This semi permeable membrane is 1/10,000 of a micron and will effectively reduce total dissolved solids, sodium and a wide range of contaminants such as arsenic, lead, percolate, chromium, copper and radium. It will also remove over 99.95 percent cysts such as giardia and cryptosporidium. Stage 4 is a high quality GAC final filter. The system is equipped with a 3 gallon capacity storage tank and a high flow chrome designer faucet.