The main ingredient in almost all water filters is activated carbon, which is a form of carbon that has been processed to make it extremely porous and thus to have a very large surface area available for absorption of chemicals and impurities.
These three carbon based water filters fit the Amana, Hotpoint, GE, Kenmore and other similar refrigerators, and are meant to replace the SmartWater filter from GE.
Their pressure ranges varies from 20 to 120 PSI, and have a capacity of 300 to 350 gallons before needing to be changed. While the SwiftGreen and WaterSentinel fridge filters are aftermarket filters, the GE filter is an original part from the manufacturer.
Flow rates on these refrigerator water filters are 0.5 gallon per minute. The optimal temperature ranges for these filters are between 33 and 100 degrees. Fridge filters are used for reducing chlorine taste, odors and impurities, and will last for about six months with normal use. They are easy to replace, as they screw on the filter, fitting without the need for tools. To test it, just run about a gallon of water to see if it needs just a bit more tightening. Because they are sold in packs of three, you may not have to make another purchase for at least a year to 18 months, making this a bargain.