Our Watts Premium quick change drinking water system is a high quality three cartridge filtration system.  It mounts under your sink, and includes it's own counter mounted faucet.  The system filters sediment down to 5 microns with the first cartridge, chlorine and other organic contaminants with the second cartridge, and small particles (smaller than bacteria) in the third cartridge.  The combination gives you outstanding filtration without removing the beneficial minerals.  Each cartridge will last for 2000 gallons or one year, whichever comes first.  When it comes time to change the cartridges, the quick change cartidges are easily removed with a twist.