The four stage Residential Series Reverse Osmosis units are configured to provide purified drinking water to a long reach faucet via a pressurized storage tank. The RO units come assembled, and include white housings, 5 micron poly sediment filter; 5 micron, 6,000 gallon carbon block; bracket, 3.2 gallon pressure tank, drain saddle, housing wrench, faucet, and a 25 gpd membrane. Detailed instructions make installation an easy DIY job!