For cold water applications from 40 F to 125 F Reduces taste of chlorine and other foul tastes and odors Cartidges with a celluose matrix (carbon impregnated cellulose) also remove fine sand, silt, scale and rust particles Carbon block cartridge offers incredibly fine filtering - down to half a micron; this cartridge is often referred to as a charcoal filter Should be replaced 3 to 4 times a year, depending on water conditions