This NSF-certified water filter helps to improve the taste, quality, and health of your water by removing a number of contaminants including mercury, lead, and trace pharmaceuticals. The filter should be replaced every six month or after 300 gallons of water have been filtered. If you are unsure if your filter is due for replacement, another indicator is if the water flow from the dispenser has slowed down considerably. Replacing this part is a simple task that does not require any tools or shutting off the water or power supply to your fridge. Once the new filter has been installed, be sure to run at least two gallons of water through before consuming.