About this item 

• GLACIER FRESH Replacement for 4204490 Filter Statement: Material and Construction and Performance Tested to NSF42 Standards. Tested & verified by independent laboratory testing, 4204490 refrigerator water filter removes 97.9% chlorine and improves water smell and taste. For more details about NSF information, please enter certified model number "GF-ZERO" or manufacturer "Ningbo Pureza Technology, LLC" on the NSF database. 
• Maintain all necessary micronutrients: After testing in our laboratory, the GF-ZERO Refrigerator Water Filter removed 97.9% of the chlorine and improved the smell and taste of the water. 
• Compatible with Sub-Zero Refrigerator Water Filter: 4204490, 4290510, 9030868, PRO 48, PRO 48 with glass door, BI-36F freezer, BI-36U up and down refrigerator/freezer, BI-48S side-by-side refrigerator/freezer, BI-48SD side-by-side Refrigerator/freezer, BI-36UG glass door refrigerator/freezer, BI-30U up and down refrigerator/freezer, BI-30UG glass door refrigerator/freezer, BI-42S side-by-side refrigerator/freezer, BI-42SD side-by-side refrigerator/freezer. 
• Twist-lock design, leak-proof fit: The water filter replacement 4204490 features a twisted design for quick and easy filter change. Leakproof fit, free of tools.
• Filter life: For optimum filtration, replace the water filter cartridge every six months or 200 gallons (depending on your actual water usage) and periodically replace the water filter for higher quality water and ice.