Authoritative certification: The material and structure of GF replacement water filter meet the NSF42 standard. You can look up the model number "GF-ULTRAWF" in the NSF database. Tested and verified by an independent laboratory, this pure source ultra replacement filter removes 97.9% of chlorine and improves the smell and taste of your water. Compatible Models: Our water filter compatible with frigidaire, replacement for ULTRAWF, Pure Source Ultra, 1000472026, 203618461, 242017800, 242017801, 242017802, 242069601, 3957684, Kenmore 46-9919 46-9999, 469999, 9919, 9999, A0094E28261 High-Quality Filter Material: This Pure Source Ultra replacement filter uses 100% coconut shell carbon blocks selected from Sri Lanka, which maximizes the filtration effect. The filter can removes impurities while retaining beneficial minerals. Long-lasting Performance: For the best performance, we recommend replacing your PureSource Ultra water filter every 6 months or after 300 gallons of water has passed through it, whichever happens first, based on your water quality. Perfect fit: Follow the instructions and install in minutes with no extra tools required. We can ensure a perfect fit and effectively solve your water needs. 1