This water cooler has a 3 stage reverse osmosis purification system. The replacement costs and part numbers are as follows:

Reverse Osmosis Replacement Filters Part Number Cost
Carbon pre-filter 4603 K $20.87
Carbon Post Filter 4603-j $12.87
RO Membrane (TFC 18 GPD) 4817-6 $35.87

Replace post and pre filters every six months or as needed. Replace membrane every 3 years for non softened water and 5 years for softened water or as needed. Reverse Osmosis System will provide up to 18 gallons of purified water per day.