The Frigidaire WF2CB PureSource2 Refrigerator water filter fits all Frigidaire refrigerators with a slide out filter cartridge. It replaces Frigidaire part numbers FC-100, FC100, and Sears Kenmore part number 46-9911, used in Kenmore refrigerators that are made by Frigidaire (model numbers starting with 253). It improves the taste and odor of the water and removes the following impurities: 99.99% of Cysts, 98.5% of Particulates (Class I), 99.70% of Turbidity, 99.30% of Lead, 98.6% of Particulates (Class III), 91% of Mercury, 96% of 1,4-D (a herbicide), 98% of Alachlor (a herbicide), 98% of Atraxine (a herbicide), 92% of Lindane (a pesticide), and 87.5% of Toxaphene (a pesticide). It Does Not Remove Flouride. Frigidaire recommends that you replace the filter every 9 months or when the filter status light turns red, whichever comes first OR if the refrigerator has not been used for more than two weeks (for instance, during a move) OR if you notice a decrease in the flow of water or objectionable tastes in the water or ice.