The PUR Water Filter Dispenser - PUR DS-1800Z - is a two-stage filtered water dispenser, which removes more contaminants than any other pour-through water filter system. It can hold up to 18 eight ounce glasses of water at one time. This PUR water dispenser removes 99.9% of microbiological cysts (cryptosporidium, giardia, etc.) and 98% of lead. It also reduces mercury, cadmium, copper, the bad taste and odor of chlorine, sediment, pharmaceutical residues, various agricultural and industrial pollutants, and other impurities. This PUR filtered dispenser does not remove beneficial flouride. The PUR DS-1800Z includes one water filter cartridge (PUR CRF-950Z) that should be changed about every 1-2 months or 40 gallons. It has a filter-life gauge which indicates when the PUR CRF-950Z filter cartridge needs to be replaced. The space saving design of this PUR water filter dispenser allows it to easily fit in your refrigerator without taking up too much space.